WO2020255198A1 - Freezing apparatus - Google Patents

Freezing apparatus Download PDF

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Publication number
WO2020255198A1
WO2020255198A1 PCT/JP2019/023880 JP2019023880W WO2020255198A1 WO 2020255198 A1 WO2020255198 A1 WO 2020255198A1 JP 2019023880 W JP2019023880 W JP 2019023880W WO 2020255198 A1 WO2020255198 A1 WO 2020255198A1
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WO
WIPO (PCT)
Prior art keywords
control
compressor
pressure
time
inverter
Prior art date
Application number
PCT/JP2019/023880
Other languages
French (fr)
Japanese (ja)
Inventor
雅浩 神田
雅章 上川
駿 岡田
Original Assignee
三菱電機株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 三菱電機株式会社 filed Critical 三菱電機株式会社
Priority to EP19933756.9A priority Critical patent/EP3985327B1/en
Priority to US17/603,648 priority patent/US20220235987A1/en
Priority to PCT/JP2019/023880 priority patent/WO2020255198A1/en
Publication of WO2020255198A1 publication Critical patent/WO2020255198A1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F25B49/022—Compressor control arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/08—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F04C18/12—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type
    • F04C18/14—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons
    • F04C18/16—Rotary-piston pumps specially adapted for elastic fluids of intermeshing-engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing of other than internal-axis type with toothed rotary pistons with helical teeth, e.g. chevron-shaped, screw type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
    • F04C18/48—Rotary-piston pumps with non-parallel axes of movement of co-operating members
    • F04C18/50—Rotary-piston pumps with non-parallel axes of movement of co-operating members the axes being arranged at an angle of 90 degrees
    • F04C18/52—Rotary-piston pumps with non-parallel axes of movement of co-operating members the axes being arranged at an angle of 90 degrees of intermeshing engagement type, i.e. with engagement of co-operating members similar to that of toothed gearing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
    • F04C28/06—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids specially adapted for stopping, starting, idling or no-load operation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C28/00—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids
    • F04C28/24—Control of, monitoring of, or safety arrangements for, pumps or pumping installations specially adapted for elastic fluids characterised by using valves controlling pressure or flow rate, e.g. discharge valves or unloading valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B13/00—Compression machines, plants or systems, with reversible cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
    • F04C2270/00—Control; Monitoring or safety arrangements
    • F04C2270/09—Electric current frequency
    • F04C2270/095—Controlled or regulated
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B1/00—Compression machines, plants or systems with non-reversible cycle
    • F25B1/04—Compression machines, plants or systems with non-reversible cycle with compressor of rotary type
    • F25B1/047—Compression machines, plants or systems with non-reversible cycle with compressor of rotary type of screw type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2500/00—Problems to be solved
    • F25B2500/27—Problems to be solved characterised by the stop of the refrigeration cycle
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/02—Compressor control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/02—Compressor control
    • F25B2600/021—Inverters therefor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/15—Control issues during shut down
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2700/00—Sensing or detecting of parameters; Sensors therefor
    • F25B2700/21—Temperatures
    • F25B2700/2115—Temperatures of a compressor or the drive means therefor
    • F25B2700/21152—Temperatures of a compressor or the drive means therefor at the discharge side of the compressor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/20—Disposition of valves, e.g. of on-off valves or flow control valves

Definitions

  • the present invention relates to a refrigerating device equipped with a screw compressor.
  • a screw compressor is known as one of the positive displacement compressors.
  • the screw compressor is used, for example, as a component of a refrigerant circuit built in a refrigerating apparatus or the like.
  • Examples of the screw compressor include a single screw compressor including one screw rotor having a spiral screw groove and one or two gate rotors having a plurality of gate rotor teeth that fit into the screw groove.
  • a plurality of compression chambers are formed by meshing and engaging the screw groove and the tooth portion of the gate rotor with each other.
  • One end of the screw rotor in the direction of the rotation axis is the suction side of the refrigerant, and the other end is the discharge side.
  • the inside of the casing in which the screw rotor and the gate rotor are housed is divided into a low pressure portion provided on the suction side of the compression chamber and a high pressure portion provided on the discharge side of the compression chamber.
  • the gate rotor teeth move in the screw groove as the screw rotor rotates, and the operation of expanding the volume of the compression chamber and the operation of reducing the volume are repeated.
  • the refrigerant is sucked into the compression chamber, and during the period when the volume of the compression chamber is reduced, the sucked refrigerant is compressed.
  • the screw groove constituting the compression chamber communicates with the discharge port, the compressed high-pressure refrigerant is discharged from the compression chamber via the discharge port.
  • Patent Document 1 discloses a technique for suppressing the reverse rotation of the screw rotor that occurs when the single screw compressor is stopped.
  • a DC voltage is applied from the inverter to the motor stator in the compressor, and rotational braking control is performed to control the motor rotor so that it does not rotate.
  • the refrigerant flows from the high pressure portion to the low pressure portion, and the high pressure portion and the low pressure portion are equalized.
  • the refrigerant passes through a small flow path such as a minute gap between the screw rotor and the casing and a small refueling hole for refueling the compression chamber by a differential pressure refueling method for the purpose of bearing lubrication or the like. It flows. Therefore, it takes a lot of time for the high pressure portion and the low pressure portion to be equalized.
  • the present invention has been made in view of the above-mentioned problems in the prior art, and is a refrigerating device capable of suppressing the driving of the compression mechanism when the braking control is completed and suppressing damage or wear of the compression mechanism.
  • the purpose is to provide.
  • the refrigerating device of the present invention is a refrigerating device including a compressor that compresses and discharges the sucked refrigerant by a compression mechanism, and includes a motor that drives the compression mechanism, a low-pressure portion through which the sucked refrigerant flows, and the above.
  • a compressor having a flow rate adjusting valve for adjusting the flow rate of the refrigerant flowing through the communication flow path, an inverter for supplying a voltage to the compressor to drive or stop the motor, and the inverter and the flow rate adjusting valve.
  • the control device includes braking control that controls the inverter to prevent or suppress the drive of the compression mechanism in stop control for stopping the operation of the compressor, and the flow control valve. Is opened to perform pressure equalization control for equalizing the pressure between the high pressure portion and the low pressure portion.
  • the present invention when the operation of the compressor is stopped, braking control is performed and pressure equalization control is performed.
  • the pressure equalizing time between the high-pressure portion and the low-pressure portion is shortened, so that the drive of the compression mechanism when the braking control is completed can be suppressed, and damage or wear of the compression mechanism can be suppressed.
  • FIG. It is a circuit diagram which shows an example of the structure of the refrigerating apparatus which concerns on Embodiment 1.
  • FIG. It is a functional block diagram which shows an example of the structure of the control device of FIG.
  • It is a hardware block diagram which shows an example of the structure of the control device of FIG.
  • It is a hardware block diagram which shows another example of the structure of the control device of FIG.
  • It is the schematic which shows the compression principle of the compressor which concerns on Embodiment 1.
  • FIG. It is a schematic diagram for demonstrating the rotational braking control and pressure equalization control in Embodiment 1.
  • FIG. It is a flowchart which shows an example of the process flow of rotation braking control and pressure equalization control in Embodiment 1.
  • Embodiment 2 It is the schematic for demonstrating the rotational braking control and pressure equalization control in Embodiment 2. It is a flowchart which shows an example of the process flow of rotation braking control and pressure equalization control in Embodiment 2. It is the schematic for demonstrating the rotational braking control and pressure equalization control in Embodiment 3. It is a flowchart which shows an example of the process flow of rotation braking control and pressure equalization control in Embodiment 3. It is a schematic diagram for demonstrating the rotational braking control and pressure equalization control in Embodiment 4. It is a flowchart which shows an example of the process flow of rotation braking control and pressure equalization control in Embodiment 4.
  • Embodiment 1 the refrigerating apparatus according to the first embodiment will be described.
  • the form of the component represented in the full text of the specification is merely an example, and is not limited to the form described in the specification.
  • the combination of components is not limited to the combination in each embodiment, and the components described in other embodiments can be applied to other embodiments.
  • the height of pressure, etc. is not determined in relation to the absolute value, but is relatively determined in the state or operation of the system, device, etc. Further, in the drawings, the relationship between the sizes of the constituent members may differ from the actual one.
  • FIG. 1 is a circuit diagram showing an example of the configuration of the refrigerating apparatus 100 according to the first embodiment.
  • the refrigerating device 100 includes a compressor 1, a condenser 2, a depressurizing device 3, an evaporator 4, an inverter 5, and a control device 6.
  • the compressor 1, the condenser 2, the depressurizing device 3, and the evaporator 4 are sequentially connected by a refrigerant pipe to form a refrigerant circuit in which the refrigerant circulates.
  • the refrigerant that circulates in the refrigerant circuit is not particularly limited, and is, for example, a fluorocarbon refrigerant such as HFC (hydrofluorocarbon) and HFO (hydrofluoroolefin), a hydrocarbon refrigerant such as HC (hydrocarbon), or CO 2. It can be applied regardless of the magnitude of operating pressure, such as (carbon dioxide) and natural refrigerants such as ammonia.
  • the compressor 1 sucks in a low-temperature low-pressure refrigerant, compresses the sucked refrigerant into a high-temperature and high-pressure state, and discharges the sucked refrigerant.
  • the compressor 1 is composed of, for example, an inverter compressor or the like whose capacity, which is the amount of transmission per unit time, is controlled by changing the operating frequency.
  • the operating frequency of the compressor 1 is controlled by the control device 6.
  • the compressor 1 is driven by supplying electric power from a power supply source (not shown) to a motor 10 described later via an inverter 5. Further, the compressor 1 has a rotation braking control function for controlling the rotation of the motor 10 at the time of stop control for stopping the operation. Specifically, in the rotation braking control function, even if a DC voltage is applied from the inverter 5 to the stator 10a described later and torque is generated in the motor 10, a force for rotating the motor rotor 10b is received. , A function of controlling the rotation of the motor 10 so as to prevent or suppress the rotation of the motor rotor 10b.
  • the compressor 1 for example, a single screw compressor in which two gate rotors are engaged with one screw rotor is applied.
  • FIG. 1 such a single screw compressor is shown.
  • the compressor 1 includes a tubular casing 1a, a motor 10, a screw shaft 11, a screw rotor 12, a gate rotor 13, and the like housed in the casing 1a.
  • the motor 10 is an inverter type electric motor whose rotation speed is controlled by the inverter 5, and drives the screw rotor 12 to rotate.
  • the motor 10 is composed of a stator 10a fixed inscribed in the casing 1a and a motor rotor 10b arranged inside the stator 10a.
  • the screw rotor 12 and the motor rotor 10b are arranged on the same axis, and are fixed to the screw shaft 11.
  • the screw shaft 11 is fixed to the motor rotor 10b and is rotationally driven by the motor 10. Both sides of the screw shaft 11 are supported by a main bearing 11a and a sub bearing 11b.
  • the screw rotor 12 is the suction side of the refrigerant, and the other end is the discharge side.
  • the screw rotor 12 is formed in a columnar shape, and a plurality of spiral screw grooves 12a (see FIG. 5 described later) are formed on the outer peripheral surface thereof.
  • the screw rotor 12 is connected to a motor rotor 10b fixed to the screw shaft 11 and is rotationally driven.
  • a pair of gate rotors 13 are arranged on the side surface of the screw rotor 12 so as to be axisymmetric with respect to the screw shaft 11.
  • the gate rotor 13 is formed in a disk shape, and a plurality of teeth 13a (see FIG. 5) extending radially along the circumferential direction are provided on the outer peripheral surface.
  • the gate rotor 13 is arranged so that the teeth 13a mesh with the screw groove 12a of the screw rotor 12.
  • the compression chamber 14 is formed in a space surrounded by the teeth 13a of the gate rotor 13, the screw groove 12a, and the inner cylinder surface of the casing 1a.
  • the configuration including the screw rotor 12, the gate rotor 13, and the compression chamber 14 formed by these may be collectively referred to as a “compression mechanism”.
  • the inside of the casing 1a is partitioned by a partition wall 1b between a low-pressure portion 15 on the refrigerant suction side where the low-pressure refrigerant is located and a high-pressure portion 16 on the refrigerant discharge side where the high-pressure refrigerant is located, including the compression chamber 14.
  • the low pressure section 15 is formed with a suction port (not shown) that opens in the flow path on the refrigerant suction side.
  • a strainer 17 is arranged at the suction port to prevent foreign matter such as dust from flowing into the compressor 1.
  • the high pressure section 16 is formed with a discharge port 1c (see FIG. 5) that opens in the flow path on the refrigerant discharge side.
  • the discharge port 1c is provided with a check valve 18 for preventing the backflow of the discharged refrigerant.
  • the check valve 18 may be externally provided on the compressor 1, or the check valve 18 may not be provided.
  • the high-pressure unit 16 contains a high-pressure refrigerant gas and refrigerating machine oil discharged from the compression chamber 14, and is used to separate the refrigerant gas discharged from the compression chamber 14 and the refrigerating machine oil.
  • An oil separator and an oil reservoir for storing the separated refrigerating machine oil are arranged.
  • the compressor 1 is provided with an oil flow path for supplying refrigerating machine oil from the oil reservoir to the compression chamber 14. Refrigerating machine oil is supplied to the compression chamber 14 by a pressure difference from an oil supply hole provided in the casing 1a through this oil flow path.
  • the refrigerant gas separated by the oil separator passes through the check valve 18 in the compressor 1 and then is discharged to the refrigerant circuit outside the compressor 1.
  • the compressor 1 is provided with a communication flow path 20 for communicating the low pressure portion 15 and the high pressure portion 16 and bypassing the fluid of the high pressure portion 16 to the low pressure portion 15.
  • the communication flow path 20 is provided with a flow rate adjusting valve 21 for adjusting the flow rate of the fluid flowing through the communication flow path 20.
  • the opening degree of the flow rate adjusting valve 21 is controlled by the control device 6.
  • the communication flow path 20 may be formed outside the compressor 1 by a copper pipe, a steel pipe, or the like, or may be formed inside the casing 1a of the compressor 1, and the means for forming the communication flow path 20 is limited. Not done.
  • Condenser 2 exchanges heat between the outdoor air supplied by a blower (not shown) and the refrigerant.
  • the condenser 2 dissipates the heat of the refrigerant to the outdoor air and condenses the refrigerant gas discharged from the compressor 1.
  • the decompression device 3 decompresses and expands the refrigerant liquid flowing out of the condenser 2.
  • the pressure reducing device 3 is composed of a valve capable of controlling the opening degree, such as an electronic expansion valve. In this case, the opening degree of the decompression device 3 is controlled by the control device 6.
  • the decompression device 3 is not limited to one capable of controlling the opening degree, and may be, for example, a capillary tube or the like.
  • the evaporator 4 exchanges heat between the air supplied by a blower (not shown) and the refrigerant.
  • the evaporator 4 evaporates the refrigerant flowing out from the decompression device 3.
  • the inverter 5 is composed of, for example, a plurality of switching elements (not shown), and converts a DC voltage into an AC voltage.
  • the motor 10 of the compressor 1 is connected to the inverter 5, and the converted AC voltage is supplied to the compressor 1.
  • the inverter 5 outputs an AC voltage, which is a PWM (Pulse Width Modulation) voltage, by being controlled by the control device 6.
  • PWM Pulse Width Modulation
  • Control device 6 The control device 6 controls the entire refrigerating device 100 including the compressor 1, the depressurizing device 3, and the inverter 5.
  • the control device 6 controls the compressor 1 and the inverter 5 to prevent or suppress the reverse rotation of the screw rotor 12 when the operation of the compressor 1 is stopped. I do.
  • the control device 6 controls the opening degree of the flow rate adjusting valve 21 to allow the refrigerant of the high pressure section 16 to flow into the low pressure section 15 via the communication flow path 20, and the pressure difference between the high pressure section 16 and the low pressure section 15. Pressure equalization control is performed to make the pressure uniform.
  • FIG. 2 is a functional block diagram showing an example of the configuration of the control device 6 of FIG.
  • the control device 6 includes a comparison determination unit 61, a drive control unit 62, and a storage unit 63.
  • the control device 6 is composed of hardware such as a circuit device that realizes various functions by executing software on an arithmetic unit such as a microcomputer. Note that, in FIG. 2, only the configuration for the function related to the first embodiment is shown, and the other configurations are not shown.
  • the comparison determination unit 61 performs various comparisons and determinations. For example, in the first embodiment, the comparison determination unit 61 determines whether or not the operating frequency of the compressor 1 has reached a preset operating frequency. Further, the comparison determination unit 61 determines whether or not the set rotation braking time has elapsed since the rotation braking control was started. Further, the comparison determination unit 61 determines whether or not the set pressure equalization time has elapsed since the pressure equalization control was started.
  • the drive control unit 62 controls the inverter 5 and the flow rate adjusting valve 21 based on the determination result of the comparison determination unit 61.
  • the storage unit 63 stores various information used in each unit of the control device 6 in advance.
  • the storage unit 63 stores the set rotation braking time and the set pressure equalization time used in the comparison determination unit 61.
  • the set rotary braking time indicates the rotary braking control time from the start to the end of the rotary braking control.
  • the set pressure equalization time indicates the pressure equalization control time from the start to the end of the pressure equalization control.
  • FIG. 3 is a hardware configuration diagram showing an example of the configuration of the control device 6 of FIG.
  • the control device 6 of FIG. 2 is composed of a processing circuit 71 as shown in FIG.
  • each function of the comparison determination unit 61, the drive control unit 62, and the storage unit 63 is realized by the processing circuit 71.
  • the processing circuit 71 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), or an FPGA (Field-Programmable Gate). Array), or a combination of these.
  • each of the functions of the comparison determination unit 61, the drive control unit 62, and the storage unit 63 may be realized by the processing circuit 71, or the functions of each part may be realized by one processing circuit 71. ..
  • FIG. 4 is a hardware configuration diagram showing another example of the configuration of the control device 6 of FIG.
  • the control device 6 of FIG. 2 is composed of a processor 81 and a memory 82 as shown in FIG.
  • each function of the comparison determination unit 61, the drive control unit 62, and the storage unit 63 is realized by the processor 81 and the memory 82.
  • the functions of the comparison determination unit 61, the drive control unit 62, and the storage unit 63 are realized by software, firmware, or a combination of software and firmware.
  • the software and firmware are written as a program and stored in the memory 82.
  • the processor 81 realizes the functions of each part by reading and executing the program stored in the memory 82.
  • RAM Random Access Memory
  • ROM Read Only Memory
  • flash memory EPROM (Erasable and Programmable ROM), EEPROM (Electrically Erasable, volatile ROM, etc.)
  • a removable recording medium such as a magnetic disk, a flexible disk, an optical disk, a CD (Compact Disc), an MD (Mini Disc), or a DVD (Digital Versaille Disc) may be used.
  • FIG. 5 is a schematic view showing the compression principle of the compressor 1 according to the first embodiment.
  • the “suction stroke”, the “compression stroke”, and the “discharge stroke” are shown in order from the left side of the paper.
  • FIG. 5 shows the state of the compression chamber 14 in the suction stroke.
  • the screw rotor 12 is driven by the motor 10 and rotates in the direction of the solid arrow, the teeth 13a of the gate rotor 13 sequentially rotate and move toward the discharge port side in conjunction with this rotation.
  • the volume of the compression chamber 14 is reduced, and the refrigerant gas in the compression chamber 14 is compressed.
  • the compression chamber 14 communicates with the discharge port 1c as shown in the figure on the right side of FIG. As a result, the high-pressure refrigerant gas compressed in the compression chamber 14 is discharged from the discharge port 1c to the high-pressure portion 16. Then, the same compression is performed again on the back surface of the screw rotor 12.
  • the compression chamber 14 formed by the casing 1a, the teeth 13a of the gate rotor 13, the screw rotor 12, and the like is provided with a minute space (not shown) for the gate rotor 13 and the screw rotor 12 to rotate.
  • This minute space is a flow path through which the high-pressure refrigerant gas compressed in the compression chamber 14 and the refrigerating machine oil supplied to the compression chamber 14 leak to the low-pressure portion 15.
  • rotational braking control is performed to control the rotation of the motor 10 so as to prevent or suppress the reverse rotation of the screw rotor 12 when the operation of the compressor 1 is stopped.
  • pressure equalization control is performed so that the refrigerant of the high pressure portion 16 flows into the low pressure portion 15 via the communication flow path 20.
  • rotational braking control and pressure equalization control will be described with reference to a specific example shown in FIG.
  • FIG. 6 is a schematic diagram for explaining rotational braking control and pressure equalization control according to the first embodiment.
  • the vertical axis of the graph indicates the command operation frequency from the inverter 5, and the horizontal axis indicates time. Further, FIG. 6 shows the state of the rotary braking control and the flow rate adjusting valve 21 corresponding to the time shown in the graph.
  • the compressor 1 is driven at a driving frequency F 2.
  • the control device 6 receives the stop command for stopping the compressor 1 from the outside, the drive control unit 62 performs stop control for the compressor 1. Then, the drive control unit 62 outputs a command to the inverter 5 so as to lower the operating frequency of the compressor 1 from F 2 to a frequency F 1 lower than F 2 .
  • the inverter 5 lowers the operating frequency of the compressor 1 from F 2 to F 1 based on a command from the drive control unit 62.
  • the control device 6 performs rotational braking control.
  • the drive control unit 62 outputs a command to the inverter 5 so as to apply a preset DC voltage to the stator 10a.
  • the inverter 5 applies a DC voltage to the stator 10a.
  • the control device 6 simultaneously performs pressure equalization control.
  • the drive control unit 62 controls the flow rate adjusting valve 21 of the compressor 1 to open.
  • the refrigerant in the high-pressure section 16 of the compressor 1 flows into the low-pressure section 15 via the communication flow path 20, the pressure difference between the high-pressure section 16 and the low-pressure section 15 is reduced, and the high-pressure section 16 and the low-pressure section 15 are reduced.
  • the pressure inside becomes uniform.
  • the control unit 6 ends the rotational braking control. Further, since the set pressure equalizing time elapses at the same time, the drive control unit 62 controls to close the flow rate adjusting valve 21 of the compressor 1. As a result, the pressure equalization control is completed.
  • the rotation braking control is performed only for the set rotation braking time stored in the storage unit 63.
  • the pressure equalization control is performed only for the set pressure equalization time stored in the storage unit 63.
  • the set rotation braking time is set to be included in the set pressure equalization time. Therefore, the pressure equalizing control is performed during the period including the period of the rotational braking control.
  • the set rotation braking time and the set pressure equalizing time are set to the same time. That is, in the first embodiment, the pressure equalizing control is started at the same time as the rotation braking control is started, and the pressure equalizing control is finished at the same time as the rotation braking control is finished.
  • FIG. 7 is a flowchart showing an example of the processing flow of the rotation braking control and the pressure equalizing control in the first embodiment.
  • step S1 the control device 6 determines whether or not a stop command for the compressor 1 has been received from the outside.
  • step S1: Yes the stop command of the compressor 1 is received
  • step S2 the process proceeds to step S2.
  • step S1: No the process returns to step S1, and the process of step S1 is repeated until the stop command is received.
  • step S2 the drive control unit 62 controls the inverter 5 so as to lower the operating frequency of the compressor 1.
  • step S3 the comparison and determination section 61, the operating frequency of the compressor 1 is determined whether the F 1.
  • step S3 When the operating frequency of the compressor 1 is F 1 (step S3: Yes), the control device 6 starts the rotation braking control in step S4. Then, in step S5, the drive control unit 62 controls to open the flow rate adjusting valve 21. On the other hand, if the operation frequency of the compressor 1 is not F 1: (the step S3 No), the process returns to step S3, the operating frequency is step S3 is repeated until the F 1.
  • step S6 the comparison determination unit 61 determines whether or not the set rotation braking time and the set pressure equalizing time have elapsed since the rotation braking control and the pressure equalizing control were started.
  • step S6: Yes the control device 6 ends the rotation braking control in step S7.
  • step S8 the control device 6 controls so as to close the flow rate adjusting valve 21 and ends the pressure equalization control.
  • step S6: No the process returns to step S6 until the set rotation braking time and the set pressure equalizing time elapse. Rotational braking control and pressure equalization control are continued.
  • the inverter 5 is controlled to perform rotational braking control, and the flow rate adjusting valve 21 is opened to perform high pressure.
  • Pressure equalization control is performed to equalize the pressure between the unit 16 and the low pressure unit 15.
  • the pressure equalization control is performed during the same period as the rotational braking control.
  • the flow rate adjusting valve 21 opens during the rotary braking control, the refrigerant flows from the high pressure portion 16 to the low pressure portion 15, and the high pressure portion 16 and the low pressure portion 15 are equalized, so that the high pressure portion 16 and the low pressure portion 15
  • the pressure equalization time can be shortened.
  • the pressure equalizing time is shortened, the reverse rotation of the screw rotor 12 after the rotation braking control is completed is prevented or suppressed, so that damage or wear of the gate rotor 13 can be suppressed. Further, since the pressure equalizing time is shortened, excessive oil outflow from the high pressure portion 16 to the low pressure portion 15 through the refueling hole is suppressed, so that the liquid compression (the next time the compressor 1 is started) is performed. It is possible to prevent damage to the gate rotor 13 due to oil compression).
  • the control device 6 controls the inverter 5 to perform rotational braking control when the operating frequency of the compressor 1 becomes a frequency F 1 lower than the operating frequency F 2 . This makes it possible to prevent damage to the compressor 1 due to suddenly stopping the compressor 1 from the operating state.
  • the communication flow path 20 may be provided outside the casing 1a of the compressor 1 or may be provided inside the casing 1a.
  • Embodiment 2 Next, the second embodiment will be described.
  • the second embodiment is different from the first embodiment in that the pressure equalizing control is continued even after the rotational braking control is completed.
  • the same reference numerals are given to the parts common to the first embodiment, and detailed description thereof will be omitted.
  • the pressure equalizing control is performed at the same time as the rotational braking control, but is continued even after the rotational braking control is completed. That is, in the second embodiment, the set pressure equalizing time is set to be longer than the set rotation braking time.
  • FIG. 8 is a schematic view for explaining rotational braking control and pressure equalization control according to the second embodiment.
  • the vertical axis of the graph indicates the command operation frequency from the inverter 5, and the horizontal axis indicates time. Further, FIG. 8 shows the state of the rotary braking control and the flow rate adjusting valve 21 corresponding to the time shown in the graph.
  • the compressor 1 is driven at a driving frequency F 2.
  • the control device 6 receives the stop command compressor 1 from the outside, the drive control unit 62 performs stop control for the compressor 1. Then, the drive control unit 62 outputs a command to the inverter 5 so as to reduce the operating frequency of the compressor 1 from F 2 to F 1 .
  • the inverter 5 lowers the operating frequency of the compressor 1 from F 2 to F 1 based on a command from the drive control unit 62.
  • the control device 6 performs rotational braking control.
  • the drive control unit 62 outputs a command to the inverter 5 so as to apply a preset DC voltage to the stator 10a. As a result, rotational braking control is performed. Further, when the rotational braking control is performed, the control device 6 performs pressure equalization control.
  • the drive control unit 62 controls the flow rate adjusting valve 21 of the compressor 1 to open.
  • the set pressure equalizing time is set longer than the set rotation braking time. That is, in the second embodiment, since the pressure equalizing control is performed at the same time as the rotational braking control is performed, it is continuously performed even after the rotational braking control is completed.
  • FIG. 9 is a flowchart showing an example of the processing flow of the rotation braking control and the pressure equalizing control in the second embodiment. Since the processes from step S1 to step S5 are the same as those in the first embodiment, the description thereof will be omitted.
  • step S16 the comparison determination unit 61 determines whether or not the set rotation braking time has elapsed since the rotation braking control was started.
  • step S16: Yes the control device 6 ends the rotation braking control in step S17.
  • step S16: No the process returns to step S16, and the rotation braking control is continued until the set rotation braking time elapses.
  • step S18 the comparison determination unit 61 determines whether or not the set pressure equalization time has elapsed since the pressure equalization control was started.
  • step S18: Yes the control device 6 ends the pressure equalization control in step S19.
  • step S18: No the process returns to step S18, and the pressure equalization control is continued until the set pressure equalization time elapses.
  • the pressure equalizing control is continued even after the rotational braking control is completed.
  • the pressure equalization is continued, so that the pressure equalization time can be further shortened.
  • Embodiment 3 Next, the third embodiment will be described.
  • the third embodiment is different from the first embodiment in that the pressure equalizing control is performed before the rotational braking control is started.
  • the parts common to the first and second embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.
  • the pressure equalizing control is performed before the rotation braking control is started, and ends at the same time as the rotation braking control ends. That is, in the third embodiment, the set pressure equalizing time is set to be longer than the set rotation braking time. Further, in the third embodiment, the set pressure equalization start time indicating the start time of the pressure equalization control is set in advance, and the set pressure equalization start time is set to a time before the start of the rotational braking control.
  • the set pressure equalization start time is stored in advance in the storage unit 63 of the control device 6.
  • the set pressure equalization start time is set to an arbitrary time before the start of the rotary braking control.
  • the set pressure equalization start time may be the timing before receiving the stop command of the compressor 1 or the timing after receiving the stop command.
  • FIG. 10 is a schematic view for explaining rotational braking control and pressure equalization control according to the third embodiment.
  • the vertical axis of the graph indicates the command operation frequency from the inverter 5, and the horizontal axis indicates time.
  • FIG. 10 shows the state of the rotary braking control and the flow rate adjusting valve 21 corresponding to the time shown in the graph.
  • the example of FIG. 10 shows a case where the set pressure equalization start time is set to the timing before receiving the stop command of the compressor 1.
  • the control unit 6 performs control pressure equalization.
  • the drive control unit 62 controls the flow rate adjusting valve 21 of the compressor 1 to open.
  • the control device 6 receives the stop command compressor 1 from the outside, the drive control unit 62 performs stop control for the compressor 1. Then, the drive control unit 62 outputs a command to the inverter 5 so as to reduce the operating frequency of the compressor 1 from F 2 to F 1 . The inverter 5 lowers the operating frequency of the compressor 1 from F 2 to F 1 based on a command from the drive control unit 62.
  • the control device 6 performs rotational braking control.
  • the drive control unit 62 outputs a command to the inverter 5 so as to apply a preset DC voltage to the stator 10a. As a result, rotational braking control is performed.
  • the control unit 6 ends the rotational braking control. Further, since the set pressure equalizing time elapses at the same time, the drive control unit 62 controls to close the flow rate adjusting valve 21 of the compressor 1. As a result, the pressure equalization control is completed.
  • the set pressure equalizing time is set longer than the set rotation braking time. Further, the set pressure equalization start time is set before the start of the rotary braking control. That is, in the third embodiment, the pressure equalizing control is performed before the rotational braking control is started.
  • FIG. 11 is a flowchart showing an example of the processing flow of the rotation braking control and the pressure equalizing control in the third embodiment.
  • the example of FIG. 11 shows a case where the set pressure equalization start time is set before the stop command of the compressor 1.
  • step S21 the comparison determination unit 61 determines whether or not the set pressure equalization start time stored in the storage unit 63 is reached.
  • step S21: Yes the drive control unit 62 controls in step S22 to open the flow rate adjusting valve 21.
  • step S21: No the process returns to step S21, and the process of step S21 is repeated until the set pressure equalization start time is reached.
  • step S23 the control device 6 determines whether or not a stop command for the compressor 1 has been received from the outside.
  • the stop command of the compressor 1 is received (step S23: Yes)
  • the drive control unit 62 controls the inverter 5 so as to lower the operating frequency of the compressor 1 in step S24.
  • step S23: No the process returns to step S23, and the process of step S23 is repeated until the stop command is received.
  • step S25 the comparison and determination unit 61, the operating frequency of the compressor 1 is determined whether the F 1.
  • the control device 6 starts the rotation braking control in step S26.
  • step S25: No the process returns to step S25, the operating frequency is step S25 is repeated until the F 1.
  • step S27 the comparison determination unit 61 determines whether or not the set rotation braking time and the set pressure equalizing time have elapsed since the rotation braking control and the pressure equalizing control were started.
  • step S27: Yes the control device 6 ends the rotation braking control in step S28.
  • step S29 the control device 6 controls to close the flow rate adjusting valve 21 and ends the pressure equalization control.
  • step S27: No the process returns to step S27 until the set rotation braking time and the set pressure equalizing time elapse. Rotational braking control and pressure equalization control are continued.
  • the pressure equalizing control is started before the rotational braking control is started.
  • the differential pressure between the high-pressure portion 16 and the low-pressure portion 15 when the rotational braking control is completed becomes small, so that the pressure equalization time between the high-pressure portion 16 and the low-pressure portion 15 can be further shortened.
  • Embodiment 4 Next, the fourth embodiment will be described.
  • the fourth embodiment is a combination of the second and third embodiments. That is, in the fourth embodiment, the pressure equalizing control is performed before the rotational braking control is started, and is continued even after the rotational braking control is completed.
  • the parts common to the first to third embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.
  • the pressure equalizing control is performed before the rotation braking control is started, and is continued even after the rotation braking control is finished. That is, in the fourth embodiment, the set pressure equalizing time is set to be longer than the set rotation braking time. Further, the set pressure equalization start time is set before the start of the rotational braking control. The set pressure equalization start time does not matter whether it is related to the stop command of the compressor 1 as in the third embodiment.
  • FIG. 12 is a schematic view for explaining rotational braking control and pressure equalization control according to the fourth embodiment.
  • the vertical axis of the graph indicates the command operation frequency from the inverter 5, and the horizontal axis indicates time. Further, FIG. 12 shows the state of the rotary braking control and the flow rate adjusting valve 21 corresponding to the time shown in the graph.
  • the control unit 6 performs control pressure equalization.
  • the drive control unit 62 controls the flow rate adjusting valve 21 of the compressor 1 to open.
  • the control device 6 receives the stop command compressor 1 from the outside, the drive control unit 62 performs stop control for the compressor 1. Then, the drive control unit 62 outputs a command to the inverter 5 so as to reduce the operating frequency of the compressor 1 from F 2 to F 1 . The inverter 5 lowers the operating frequency of the compressor 1 from F 2 to F 1 based on a command from the drive control unit 62.
  • the control device 6 performs rotational braking control.
  • the drive control unit 62 outputs a command to the inverter 5 so as to apply a preset DC voltage to the stator 10a. As a result, rotational braking control is performed.
  • the set pressure equalizing time is set longer than the set rotation braking time. Further, the set pressure equalization start time is set before the start of the rotary braking control. That is, in the fourth embodiment, the pressure equalizing control is performed before the rotational braking control is started, and is continuously performed even after the rotational braking control is completed.
  • FIG. 13 is a flowchart showing an example of the processing flow of the rotation braking control and the pressure equalizing control in the fourth embodiment.
  • the example of FIG. 13 shows a case where the set pressure equalizing start time is set before the stop command of the compressor 1.
  • the pressure equalization control and the rotational braking control are started by performing the processes of steps S21 to S26 shown in FIG. 11 as in the third embodiment. Then, similarly to the second embodiment, the processing of steps S16 to S19 shown in FIG. 9 is performed, so that the rotation braking control and the pressure equalizing control are completed.
  • the pressure equalizing control is started before the rotational braking control is started, and is continued even after the rotational braking control is completed.
  • the pressure equalizing time between the high-voltage portion 16 and the low-voltage portion 15 can be further shortened, and damage to the inverter 5 can be suppressed.
  • the refrigerating apparatus 100 is not limited to the above-described first to fourth embodiments, and various modifications and applications are made without departing from the gist. Is possible.
  • the compressor 1 for example, a twin screw compressor having two screw rotors and engaging the grooves of the respective screw rotors to form a compression chamber may be applied.
  • a reciprocating compressor, a scroll compressor, a turbo compressor and a rotary compressor may be applied.
  • the inverter 5 is described as being configured separately from the compressor 1, but the present invention is not limited to this.
  • the inverter 5 is integrally configured with the compressor 1. You may.

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  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
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Abstract

A freezing apparatus provided with a compressor that compresses and discharges a drawn-in refrigerant by means of a compression mechanism, the freezing apparatus being provided with: the compressor, which has a motor that drives the compression mechanism, a low-pressure part through which the drawn-in refrigerant flows, a compression chamber in which the refrigerant flowing through the low-pressure part is compressed, a high-pressure part through which the refrigerant compressed in the compression chamber flows, a connecting flow path by which the low-pressure part and the high-pressure part are connected, and a flow rate adjustment valve that is provided to the connecting flow path and that adjusts the flow rate of the refrigerant flowing through the connecting flow path; an inverter that supplies a voltage to the compressor, and drives or stops the motor; and a control device that controls the inverter and the flow rate adjustment valve. In a stopping control for stopping the operation of the compressor, the control device performs a braking control for controlling the inverter to prevent or suppress driving of the compressing mechanism, and a pressure equalization control for opening the flow rate adjustment valve to equalize the pressure in the high-pressure part and the low-pressure part.

Description

冷凍装置Refrigeration equipment
　本発明は、スクリュー圧縮機を備えた冷凍装置に関するものである。 The present invention relates to a refrigerating device equipped with a screw compressor.
　従来、容積形圧縮機の一つとして、スクリュー圧縮機が知られている。スクリュー圧縮機は、例えば、冷凍装置等に内蔵された冷媒回路の構成部品として使用されている。スクリュー圧縮機としては、例えば螺旋状のスクリュー溝を有する１つのスクリューロータと、スクリュー溝に嵌まり合う複数のゲートロータ歯部を有する１つまたは２つのゲートロータとを備えたシングルスクリュー圧縮機が知られている。 Conventionally, a screw compressor is known as one of the positive displacement compressors. The screw compressor is used, for example, as a component of a refrigerant circuit built in a refrigerating apparatus or the like. Examples of the screw compressor include a single screw compressor including one screw rotor having a spiral screw groove and one or two gate rotors having a plurality of gate rotor teeth that fit into the screw groove. Are known.
　シングルスクリュー圧縮機では、スクリュー溝とゲートロータ歯部とが相互に噛み合い、係合されることによって複数の圧縮室が形成されている。スクリューロータは、回転軸方向における一端が冷媒の吸入側であり、他端が吐出側となる。スクリューロータおよびゲートロータが収納されるケーシングの内部は、圧縮室の吸入側に設けられた低圧部と、圧縮室の吐出側に設けられた高圧部とに区画されている。 In a single screw compressor, a plurality of compression chambers are formed by meshing and engaging the screw groove and the tooth portion of the gate rotor with each other. One end of the screw rotor in the direction of the rotation axis is the suction side of the refrigerant, and the other end is the discharge side. The inside of the casing in which the screw rotor and the gate rotor are housed is divided into a low pressure portion provided on the suction side of the compression chamber and a high pressure portion provided on the discharge side of the compression chamber.
　シングルスクリュー圧縮機では、スクリューロータの回転に伴ってゲートロータ歯部がスクリュー溝を移動し、圧縮室の容積が拡大する動作と、縮小する動作とが繰り返される。圧縮室の容積が拡大する期間では、冷媒が圧縮室に吸入され、圧縮室の容積が縮小する期間では、吸入された冷媒が圧縮される。そして、圧縮室を構成するスクリュー溝が吐出口に連通すると、圧縮された高圧冷媒が吐出口を介して圧縮室から吐出される。 In a single screw compressor, the gate rotor teeth move in the screw groove as the screw rotor rotates, and the operation of expanding the volume of the compression chamber and the operation of reducing the volume are repeated. During the period when the volume of the compression chamber is increased, the refrigerant is sucked into the compression chamber, and during the period when the volume of the compression chamber is reduced, the sucked refrigerant is compressed. Then, when the screw groove constituting the compression chamber communicates with the discharge port, the compressed high-pressure refrigerant is discharged from the compression chamber via the discharge port.
　シングルスクリュー圧縮機が運転中の場合、ゲートロータ歯部の周方向に対向する一対の側面のうち、ゲートロータ歯部がスクリュー溝に噛み合った状態で吸入側に位置する吸入側側面と、スクリュー溝の壁部とが接触しながらスクリューロータが回転する。一方、シングルスクリュー圧縮機が停止した場合、冷媒の圧力差によってスクリューロータが逆回転する。スクリューロータが逆回転すると、ゲートロータ歯部の一対の側面のうち吐出側側面とスクリュー溝の壁部とが接触しながらスクリューロータが回転する。この逆回転に起因してゲートロータに損傷または摩耗が生じる虞がある。 When the single screw compressor is in operation, of the pair of side surfaces facing the gate rotor teeth in the circumferential direction, the suction side side surface located on the suction side with the gate rotor teeth meshing with the screw groove and the screw groove The screw rotor rotates while contacting the wall part of the screw rotor. On the other hand, when the single screw compressor is stopped, the screw rotor rotates in the reverse direction due to the pressure difference of the refrigerant. When the screw rotor rotates in the reverse direction, the screw rotor rotates while the discharge side side surface of the pair of side surfaces of the gate rotor tooth portion and the wall portion of the screw groove come into contact with each other. The gate rotor may be damaged or worn due to this reverse rotation.
　特許文献１には、シングルスクリュー圧縮機が停止した場合に発生するスクリューロータの逆回転を抑制する技術が開示されている。特許文献１に記載のシングルスクリュー圧縮機では、インバータから圧縮機内のモータステータへ直流電圧を印加し、モータロータが回転しないように制御する回転制動制御が行われる。 Patent Document 1 discloses a technique for suppressing the reverse rotation of the screw rotor that occurs when the single screw compressor is stopped. In the single screw compressor described in Patent Document 1, a DC voltage is applied from the inverter to the motor stator in the compressor, and rotational braking control is performed to control the motor rotor so that it does not rotate.
特開２０００－２８７４８５号公報Japanese Unexamined Patent Publication No. 2000-287485
　ところで、特許文献１に記載された回転制動制御の際には、高圧部から低圧部へと冷媒が流入し、高圧部と低圧部とが均圧される。このとき、冷媒は、スクリューロータとケーシングとの間の微小な隙間、ならびに、軸受潤滑等を目的として差圧給油方式により圧縮室内へ給油している小さな給油穴といった、わずかな流路を介して流れる。そのため、高圧部と低圧部とが均圧されるには、多くの時間を要する。 By the way, in the case of the rotary braking control described in Patent Document 1, the refrigerant flows from the high pressure portion to the low pressure portion, and the high pressure portion and the low pressure portion are equalized. At this time, the refrigerant passes through a small flow path such as a minute gap between the screw rotor and the casing and a small refueling hole for refueling the compression chamber by a differential pressure refueling method for the purpose of bearing lubrication or the like. It flows. Therefore, it takes a lot of time for the high pressure portion and the low pressure portion to be equalized.
　そして、高圧部と低圧部とが均圧されるまでの間は、高圧部から圧縮室へ給油され続けてしまう。そのため、圧縮室から低圧部に油が流出し、次に圧縮機を起動させる際には、圧縮室内に多量の油が吸入され、液圧縮（油圧縮）を起こしてゲートロータが破損する虞がある。 Then, until the high pressure part and the low pressure part are equalized, the high pressure part continues to supply oil to the compression chamber. Therefore, when oil flows out from the compression chamber to the low pressure part and the compressor is started next time, a large amount of oil is sucked into the compression chamber, which may cause liquid compression (oil compression) and damage the gate rotor. is there.
　また、制動制御時間に制限があるインバータにおいて、制限時間内に高圧部と低圧部が均圧することができなかった場合には、制動制御が終了するとともにスクリューロータが逆回転し、ゲートロータが損傷または摩耗する虞がある。 Further, in an inverter having a limited braking control time, if the high pressure part and the low pressure part cannot be equalized within the time limit, the braking control is completed and the screw rotor rotates in the reverse direction, damaging the gate rotor. Or there is a risk of wear.
　本発明は、上記従来の技術における課題に鑑みてなされたものであって、制動制御が終了した際の圧縮機構の駆動を抑制し、圧縮機構の損傷または摩耗を抑制することができる冷凍装置を提供することを目的とする。 The present invention has been made in view of the above-mentioned problems in the prior art, and is a refrigerating device capable of suppressing the driving of the compression mechanism when the braking control is completed and suppressing damage or wear of the compression mechanism. The purpose is to provide.
　本発明の冷凍装置は、吸入した冷媒を圧縮機構により圧縮して吐出する圧縮機を備えた冷凍装置であって、前記圧縮機構を駆動するモータと、吸入された冷媒が流れる低圧部と、前記低圧部を流れる前記冷媒を圧縮する圧縮室と、前記圧縮室で圧縮された冷媒が流れる高圧部と、前記低圧部と前記高圧部とを連通させる連通流路と、前記連通流路に設けられ、前記連通流路を流れる前記冷媒の流量を調整する流量調整弁とを有する圧縮機と、前記圧縮機に電圧を供給し、前記モータを駆動または停止させるインバータと、前記インバータおよび前記流量調整弁を制御する制御装置とを備え、前記制御装置は、前記圧縮機の運転を停止させる停止制御において、前記インバータを制御して前記圧縮機構の駆動を防止または抑制する制動制御と、前記流量調整弁を開いて前記高圧部と前記低圧部とを均圧する均圧制御とを行うものである。 The refrigerating device of the present invention is a refrigerating device including a compressor that compresses and discharges the sucked refrigerant by a compression mechanism, and includes a motor that drives the compression mechanism, a low-pressure portion through which the sucked refrigerant flows, and the above. A compression chamber for compressing the refrigerant flowing through the low-pressure section, a high-pressure section for flowing the refrigerant compressed in the compression chamber, a communication flow path for communicating the low-pressure section and the high-pressure section, and a communication flow path provided in the communication flow path. A compressor having a flow rate adjusting valve for adjusting the flow rate of the refrigerant flowing through the communication flow path, an inverter for supplying a voltage to the compressor to drive or stop the motor, and the inverter and the flow rate adjusting valve. The control device includes braking control that controls the inverter to prevent or suppress the drive of the compression mechanism in stop control for stopping the operation of the compressor, and the flow control valve. Is opened to perform pressure equalization control for equalizing the pressure between the high pressure portion and the low pressure portion.
　本発明によれば、圧縮機の運転が停止した際に、制動制御が行われるとともに、均圧制御が行われる。これにより、高圧部と低圧部との均圧時間が短縮されるため、制動制御が終了した際の圧縮機構の駆動を抑制し、圧縮機構の損傷または摩耗を抑制することができる。 According to the present invention, when the operation of the compressor is stopped, braking control is performed and pressure equalization control is performed. As a result, the pressure equalizing time between the high-pressure portion and the low-pressure portion is shortened, so that the drive of the compression mechanism when the braking control is completed can be suppressed, and damage or wear of the compression mechanism can be suppressed.
実施の形態１に係る冷凍装置の構成の一例を示す回路図である。It is a circuit diagram which shows an example of the structure of the refrigerating apparatus which concerns on Embodiment 1. FIG. 図１の制御装置の構成の一例を示す機能ブロック図である。It is a functional block diagram which shows an example of the structure of the control device of FIG. 図２の制御装置の構成の一例を示すハードウェア構成図である。It is a hardware block diagram which shows an example of the structure of the control device of FIG. 図２の制御装置の構成の他の例を示すハードウェア構成図である。It is a hardware block diagram which shows another example of the structure of the control device of FIG. 実施の形態１に係る圧縮機の圧縮原理を示す概略図である。It is the schematic which shows the compression principle of the compressor which concerns on Embodiment 1. FIG. 実施の形態１における回転制動制御および均圧制御について説明するための概略図である。It is a schematic diagram for demonstrating the rotational braking control and pressure equalization control in Embodiment 1. FIG. 実施の形態１における回転制動制御および均圧制御の処理の流れの一例を示すフローチャートである。It is a flowchart which shows an example of the process flow of rotation braking control and pressure equalization control in Embodiment 1. 実施の形態２における回転制動制御および均圧制御について説明するための概略図である。It is the schematic for demonstrating the rotational braking control and pressure equalization control in Embodiment 2. 実施の形態２における回転制動制御および均圧制御の処理の流れの一例を示すフローチャートである。It is a flowchart which shows an example of the process flow of rotation braking control and pressure equalization control in Embodiment 2. 実施の形態３における回転制動制御および均圧制御について説明するための概略図である。It is the schematic for demonstrating the rotational braking control and pressure equalization control in Embodiment 3. 実施の形態３における回転制動制御および均圧制御の処理の流れの一例を示すフローチャートである。It is a flowchart which shows an example of the process flow of rotation braking control and pressure equalization control in Embodiment 3. 実施の形態４における回転制動制御および均圧制御について説明するための概略図である。It is a schematic diagram for demonstrating the rotational braking control and pressure equalization control in Embodiment 4. 実施の形態４における回転制動制御および均圧制御の処理の流れの一例を示すフローチャートである。It is a flowchart which shows an example of the process flow of rotation braking control and pressure equalization control in Embodiment 4.
実施の形態１．
　以下、本実施の形態１に係る冷凍装置について説明する。以下の図面において、同一の参照符号を付したものは、同一またはこれに相当するものであり、このことは、明細書の全文において共通することである。そして、明細書全文に表されている構成要素の形態は、あくまでも例示であって、明細書に記載された形態に限定するものではない。特に、構成要素の組み合わせは、各実施の形態における組み合わせのみに限定するものではなく、他の実施の形態に記載した構成要素を別の実施の形態に適用することができる。また、圧力等の高低については、特に絶対的な値との関係で定まっているものではなく、システムおよび装置等における状態あるいは動作等において相対的に定まるものとする。さらに、図面では各構成部材の大きさの関係が実際のものとは異なる場合がある。 Embodiment 1.
Hereinafter, the refrigerating apparatus according to the first embodiment will be described. In the drawings below, those with the same reference numerals are the same or equivalent, which is common throughout the specification. The form of the component represented in the full text of the specification is merely an example, and is not limited to the form described in the specification. In particular, the combination of components is not limited to the combination in each embodiment, and the components described in other embodiments can be applied to other embodiments. In addition, the height of pressure, etc. is not determined in relation to the absolute value, but is relatively determined in the state or operation of the system, device, etc. Further, in the drawings, the relationship between the sizes of the constituent members may differ from the actual one.
［冷凍装置１００の構成］
　図１は、本実施の形態１に係る冷凍装置１００の構成の一例を示す回路図である。図１に示すように、冷凍装置１００は、圧縮機１、凝縮器２、減圧装置３、蒸発器４、インバータ５および制御装置６を含んで構成されている。冷凍装置１００では、圧縮機１、凝縮器２、減圧装置３および蒸発器４が冷媒配管によって順次接続されることにより、冷媒が循環する冷媒回路が形成されている。 [Structure of Refrigerating Device 100]
FIG. 1 is a circuit diagram showing an example of the configuration of the refrigerating apparatus 100 according to the first embodiment. As shown in FIG. 1, the refrigerating device 100 includes a compressor 1, a condenser 2, a depressurizing device 3, an evaporator 4, an inverter 5, and a control device 6. In the refrigerating device 100, the compressor 1, the condenser 2, the depressurizing device 3, and the evaporator 4 are sequentially connected by a refrigerant pipe to form a refrigerant circuit in which the refrigerant circulates.
　冷媒回路を循環する冷媒は、特に限定されるものではなく、例えば、ＨＦＣ（ハイドロフルオロカーボン）およびＨＦＯ（ハイドロフルオロオレフィン）等のフルオロカーボン冷媒、ＨＣ（炭化水素）等の炭化水素冷媒、あるいは、ＣＯ２（二酸化炭素）およびアンモニア等の自然冷媒など、作動圧力の大きさに関わらず適用することができる。 The refrigerant that circulates in the refrigerant circuit is not particularly limited, and is, for example, a fluorocarbon refrigerant such as HFC (hydrofluorocarbon) and HFO (hydrofluoroolefin), a hydrocarbon refrigerant such as HC (hydrocarbon), or CO 2. It can be applied regardless of the magnitude of operating pressure, such as (carbon dioxide) and natural refrigerants such as ammonia.
（圧縮機１）
　圧縮機１は、低温低圧の冷媒を吸入し、吸入した冷媒を圧縮して高温高圧の状態にして吐出する。圧縮機１は、例えば、運転周波数を変化させることにより、単位時間あたりの送出量である容量が制御されるインバータ圧縮機等からなる。圧縮機１の運転周波数は、制御装置６によって制御される。 (Compressor 1)
The compressor 1 sucks in a low-temperature low-pressure refrigerant, compresses the sucked refrigerant into a high-temperature and high-pressure state, and discharges the sucked refrigerant. The compressor 1 is composed of, for example, an inverter compressor or the like whose capacity, which is the amount of transmission per unit time, is controlled by changing the operating frequency. The operating frequency of the compressor 1 is controlled by the control device 6.
　圧縮機１は、図示しない電力供給源からインバータ５を介して、後述するモータ１０へ電力供給されることにより駆動される。また、圧縮機１は、運転を停止させる停止制御の際に、モータ１０の回転を制御する回転制動制御機能を備えている。具体的には、回転制動制御機能は、インバータ５から後述するステータ１０ａに対して直流電圧が印加され、モータ１０にトルクが発生することにより、モータロータ１０ｂを回転させようとする力を受けても、モータロータ１０ｂの回転を防止または抑制するように、モータ１０の回転を制御する機能である。 The compressor 1 is driven by supplying electric power from a power supply source (not shown) to a motor 10 described later via an inverter 5. Further, the compressor 1 has a rotation braking control function for controlling the rotation of the motor 10 at the time of stop control for stopping the operation. Specifically, in the rotation braking control function, even if a DC voltage is applied from the inverter 5 to the stator 10a described later and torque is generated in the motor 10, a force for rotating the motor rotor 10b is received. , A function of controlling the rotation of the motor 10 so as to prevent or suppress the rotation of the motor rotor 10b.
　本実施の形態１に係る圧縮機１として、例えば、１つのスクリューロータに２つのゲートロータが係合されたシングルスクリュー圧縮機が適用される。図１では、このようなシングルスクリュー圧縮機が示されている。 As the compressor 1 according to the first embodiment, for example, a single screw compressor in which two gate rotors are engaged with one screw rotor is applied. In FIG. 1, such a single screw compressor is shown.
　圧縮機１は、筒状のケーシング１ａと、ケーシング１ａ内に収容されたモータ１０、スクリュー軸１１、スクリューロータ１２およびゲートロータ１３等を備えている。モータ１０は、インバータ５によって回転数が制御されるインバータ式の電動機であり、スクリューロータ１２を回転駆動する。モータ１０は、ケーシング１ａに内接して固定されたステータ１０ａと、ステータ１０ａの内側に配置されたモータロータ１０ｂとで構成されている。 The compressor 1 includes a tubular casing 1a, a motor 10, a screw shaft 11, a screw rotor 12, a gate rotor 13, and the like housed in the casing 1a. The motor 10 is an inverter type electric motor whose rotation speed is controlled by the inverter 5, and drives the screw rotor 12 to rotate. The motor 10 is composed of a stator 10a fixed inscribed in the casing 1a and a motor rotor 10b arranged inside the stator 10a.
　スクリューロータ１２とモータロータ１０ｂとは、互いに同一軸線上に配置され、それぞれスクリュー軸１１に固定されている。スクリュー軸１１は、モータロータ１０ｂに固定され、モータ１０によって回転駆動される。スクリュー軸１１の両側は、主軸受１１ａおよび副軸受１１ｂによって支持されている。 The screw rotor 12 and the motor rotor 10b are arranged on the same axis, and are fixed to the screw shaft 11. The screw shaft 11 is fixed to the motor rotor 10b and is rotationally driven by the motor 10. Both sides of the screw shaft 11 are supported by a main bearing 11a and a sub bearing 11b.
　スクリューロータ１２は、一端が冷媒の吸入側となり、他端が吐出側となっている。
　スクリューロータ１２は、円柱状に形成され、外周面に複数の螺旋状のスクリュー溝１２ａ（後述の図５参照）が形成されている。スクリューロータ１２は、スクリュー軸１１に固定されたモータロータ１０ｂに連結されて回転駆動される。 One end of the screw rotor 12 is the suction side of the refrigerant, and the other end is the discharge side.
The screw rotor 12 is formed in a columnar shape, and a plurality of spiral screw grooves 12a (see FIG. 5 described later) are formed on the outer peripheral surface thereof. The screw rotor 12 is connected to a motor rotor 10b fixed to the screw shaft 11 and is rotationally driven.
　スクリューロータ１２の側面には、スクリュー軸１１に対して軸対称となるように、一対のゲートロータ１３が配置されている。ゲートロータ１３は、円板状に形成され、外周面に、周方向に沿って放射状に延びる複数の歯１３ａ（図５参照）が設けられている。ゲートロータ１３は、歯１３ａがスクリューロータ１２のスクリュー溝１２ａと噛み合うように配置されている。そして、ゲートロータ１３の歯１３ａと、スクリュー溝１２ａと、ケーシング１ａの内筒面とで囲まれた空間で、圧縮室１４が形成されている。なお、以下の説明では、スクリューロータ１２、ゲートロータ１３およびこれらによって形成される圧縮室１４を含む構成を総称して「圧縮機構」と称することがある。 A pair of gate rotors 13 are arranged on the side surface of the screw rotor 12 so as to be axisymmetric with respect to the screw shaft 11. The gate rotor 13 is formed in a disk shape, and a plurality of teeth 13a (see FIG. 5) extending radially along the circumferential direction are provided on the outer peripheral surface. The gate rotor 13 is arranged so that the teeth 13a mesh with the screw groove 12a of the screw rotor 12. The compression chamber 14 is formed in a space surrounded by the teeth 13a of the gate rotor 13, the screw groove 12a, and the inner cylinder surface of the casing 1a. In the following description, the configuration including the screw rotor 12, the gate rotor 13, and the compression chamber 14 formed by these may be collectively referred to as a “compression mechanism”.
　ケーシング１ａ内部は、低圧冷媒が位置する冷媒吸入側の低圧部１５と、圧縮室１４を含む、高圧冷媒が位置する冷媒吐出側の高圧部１６とに隔壁１ｂによって区画されている。低圧部１５には、冷媒吸入側の流路に開口する図示しない吸入口が形成されている。吸入口には、圧縮機１内へのダスト等の異物の流入を防ぐためのストレーナ１７が配置されている。 The inside of the casing 1a is partitioned by a partition wall 1b between a low-pressure portion 15 on the refrigerant suction side where the low-pressure refrigerant is located and a high-pressure portion 16 on the refrigerant discharge side where the high-pressure refrigerant is located, including the compression chamber 14. The low pressure section 15 is formed with a suction port (not shown) that opens in the flow path on the refrigerant suction side. A strainer 17 is arranged at the suction port to prevent foreign matter such as dust from flowing into the compressor 1.
　高圧部１６には、冷媒吐出側の流路に開口する吐出口１ｃ（図５参照）が形成されている。吐出口１ｃには、吐出した冷媒の逆流を防止するための逆止弁１８が設けられている。なお、逆止弁１８は、圧縮機１に外付けで設けられてもよいし、逆止弁１８が設けられていなくてもよい。 The high pressure section 16 is formed with a discharge port 1c (see FIG. 5) that opens in the flow path on the refrigerant discharge side. The discharge port 1c is provided with a check valve 18 for preventing the backflow of the discharged refrigerant. The check valve 18 may be externally provided on the compressor 1, or the check valve 18 may not be provided.
　また、いずれも図示しないが、高圧部１６には、圧縮室１４から吐出された高圧の冷媒ガスおよび冷凍機油が存在し、圧縮室１４から吐出された冷媒ガスと冷凍機油とを分離するための油分離器と、分離された冷凍機油を貯留する油溜め部が配置されている。さらに、圧縮機１内には、油溜め部から圧縮室１４へ冷凍機油を供給するための油流路が設けられている。冷凍機油は、この油流路を通って、ケーシング１ａに設けられた給油穴から、圧力差によって圧縮室１４へ供給される。一方、油分離器で分離された冷媒ガスは、圧縮機１内の逆止弁１８を通過した後、圧縮機１の外部である冷媒回路に吐出される。 Further, although none of them is shown, the high-pressure unit 16 contains a high-pressure refrigerant gas and refrigerating machine oil discharged from the compression chamber 14, and is used to separate the refrigerant gas discharged from the compression chamber 14 and the refrigerating machine oil. An oil separator and an oil reservoir for storing the separated refrigerating machine oil are arranged. Further, the compressor 1 is provided with an oil flow path for supplying refrigerating machine oil from the oil reservoir to the compression chamber 14. Refrigerating machine oil is supplied to the compression chamber 14 by a pressure difference from an oil supply hole provided in the casing 1a through this oil flow path. On the other hand, the refrigerant gas separated by the oil separator passes through the check valve 18 in the compressor 1 and then is discharged to the refrigerant circuit outside the compressor 1.
　本実施の形態１において、圧縮機１には、低圧部１５と高圧部１６とを連通し、高圧部１６の流体を低圧部１５へバイパスするための連通流路２０が設けられている。連通流路２０には、連通流路２０を流れる流体の流量を調整するための流量調整弁２１が設けられている。流量調整弁２１の開度は、制御装置６によって制御される。なお、連通流路２０は、銅配管または鋼管等によって圧縮機１の外部に形成されてもよいし、圧縮機１のケーシング１ａ内部に形成されてもよく、連通流路２０の形成手段は限定されない。 In the first embodiment, the compressor 1 is provided with a communication flow path 20 for communicating the low pressure portion 15 and the high pressure portion 16 and bypassing the fluid of the high pressure portion 16 to the low pressure portion 15. The communication flow path 20 is provided with a flow rate adjusting valve 21 for adjusting the flow rate of the fluid flowing through the communication flow path 20. The opening degree of the flow rate adjusting valve 21 is controlled by the control device 6. The communication flow path 20 may be formed outside the compressor 1 by a copper pipe, a steel pipe, or the like, or may be formed inside the casing 1a of the compressor 1, and the means for forming the communication flow path 20 is limited. Not done.
（凝縮器２）
　凝縮器２は、図示しない送風機によって供給される室外空気と冷媒との間で熱交換を行う。凝縮器２は、冷媒の熱を室外空気に放熱し、圧縮機１から吐出された冷媒ガスを凝縮させる。 (Condenser 2)
The condenser 2 exchanges heat between the outdoor air supplied by a blower (not shown) and the refrigerant. The condenser 2 dissipates the heat of the refrigerant to the outdoor air and condenses the refrigerant gas discharged from the compressor 1.
（減圧装置３）
　減圧装置３は、凝縮器２から流出した冷媒液を減圧して膨張させる。減圧装置３は、例えば、電子式膨張弁等の開度の制御が可能な弁で構成される。この場合、減圧装置３の開度は、制御装置６によって制御される。なお、減圧装置３は、開度制御が可能なものに限られず、例えば、キャピラリチューブ等であってもよい。 (Decompression device 3)
The decompression device 3 decompresses and expands the refrigerant liquid flowing out of the condenser 2. The pressure reducing device 3 is composed of a valve capable of controlling the opening degree, such as an electronic expansion valve. In this case, the opening degree of the decompression device 3 is controlled by the control device 6. The decompression device 3 is not limited to one capable of controlling the opening degree, and may be, for example, a capillary tube or the like.
（蒸発器４）
　蒸発器４は、図示しない送風機によって供給される空気と冷媒との間で熱交換を行う。蒸発器４は、減圧装置３から流出した冷媒を蒸発させる。 (Evaporator 4)
The evaporator 4 exchanges heat between the air supplied by a blower (not shown) and the refrigerant. The evaporator 4 evaporates the refrigerant flowing out from the decompression device 3.
（インバータ５）
　インバータ５は、例えば、図示しない複数のスイッチング素子で構成され、直流電圧を交流電圧に変換する。インバータ５には、圧縮機１のモータ１０が接続され、圧縮機１に対して変換した交流電圧を供給する。インバータ５は、制御装置６によって制御されることにより、ＰＷＭ（Ｐｕｌｓｅ　Ｗｉｄｔｈ　Ｍｏｄｕｌａｔｉｏｎ）電圧である交流電圧を出力する。 (Inverter 5)
The inverter 5 is composed of, for example, a plurality of switching elements (not shown), and converts a DC voltage into an AC voltage. The motor 10 of the compressor 1 is connected to the inverter 5, and the converted AC voltage is supplied to the compressor 1. The inverter 5 outputs an AC voltage, which is a PWM (Pulse Width Modulation) voltage, by being controlled by the control device 6.
（制御装置６）
　制御装置６は、圧縮機１、減圧装置３およびインバータ５を含む冷凍装置１００全体を制御する。特に、本実施の形態１において、制御装置６は、圧縮機１の運転を停止させる際に、圧縮機１およびインバータ５を制御して、スクリューロータ１２の逆回転を防止または抑制する回転制動制御を行う。また、制御装置６は、流量調整弁２１の開度を制御して、連通流路２０を介して高圧部１６の冷媒を低圧部１５へ流入させ、高圧部１６と低圧部１５との圧力差を均一化する均圧制御を行う。 (Control device 6)
The control device 6 controls the entire refrigerating device 100 including the compressor 1, the depressurizing device 3, and the inverter 5. In particular, in the first embodiment, the control device 6 controls the compressor 1 and the inverter 5 to prevent or suppress the reverse rotation of the screw rotor 12 when the operation of the compressor 1 is stopped. I do. Further, the control device 6 controls the opening degree of the flow rate adjusting valve 21 to allow the refrigerant of the high pressure section 16 to flow into the low pressure section 15 via the communication flow path 20, and the pressure difference between the high pressure section 16 and the low pressure section 15. Pressure equalization control is performed to make the pressure uniform.
　図２は、図１の制御装置６の構成の一例を示す機能ブロック図である。図２に示すように、制御装置６は、比較判定部６１、駆動制御部６２および記憶部６３を備えている。制御装置６は、マイクロコンピュータなどの演算装置上でソフトウェアを実行することにより各種機能が実現され、もしくは各種機能を実現する回路デバイスなどのハードウェア等で構成されている。なお、図２では、本実施の形態１に関連する機能についての構成のみを図示し、それ以外の構成については図示を省略する。 FIG. 2 is a functional block diagram showing an example of the configuration of the control device 6 of FIG. As shown in FIG. 2, the control device 6 includes a comparison determination unit 61, a drive control unit 62, and a storage unit 63. The control device 6 is composed of hardware such as a circuit device that realizes various functions by executing software on an arithmetic unit such as a microcomputer. Note that, in FIG. 2, only the configuration for the function related to the first embodiment is shown, and the other configurations are not shown.
　比較判定部６１は、各種の比較および判定を行う。例えば、本実施の形態１において、比較判定部６１は、圧縮機１の運転周波数が予め設定された運転周波数になったか否かを判定する。また、比較判定部６１は、回転制動制御が開始されてから設定回転制動時間が経過したか否かを判定する。さらに、比較判定部６１は、均圧制御が開始されてから設定均圧時間が経過したか否かを判定する。 The comparison determination unit 61 performs various comparisons and determinations. For example, in the first embodiment, the comparison determination unit 61 determines whether or not the operating frequency of the compressor 1 has reached a preset operating frequency. Further, the comparison determination unit 61 determines whether or not the set rotation braking time has elapsed since the rotation braking control was started. Further, the comparison determination unit 61 determines whether or not the set pressure equalization time has elapsed since the pressure equalization control was started.
　駆動制御部６２は、比較判定部６１の判定結果に基づき、インバータ５および流量調整弁２１を制御する。 The drive control unit 62 controls the inverter 5 and the flow rate adjusting valve 21 based on the determination result of the comparison determination unit 61.
　記憶部６３は、制御装置６の各部で用いられる各種の情報が予め記憶されている。本実施の形態１において、記憶部６３は、比較判定部６１で用いられる設定回転制動時間および設定均圧時間を記憶している。設定回転制動時間は、回転制動制御が開始されてから終了するまでの回転制動制御時間を示す。設定均圧時間は、均圧制御が開始されてから終了するまでの均圧制御時間を示す。 The storage unit 63 stores various information used in each unit of the control device 6 in advance. In the first embodiment, the storage unit 63 stores the set rotation braking time and the set pressure equalization time used in the comparison determination unit 61. The set rotary braking time indicates the rotary braking control time from the start to the end of the rotary braking control. The set pressure equalization time indicates the pressure equalization control time from the start to the end of the pressure equalization control.
　図３は、図２の制御装置６の構成の一例を示すハードウェア構成図である。制御装置６の各種機能がハードウェアで実行される場合、図２の制御装置６は、図３に示すように、処理回路７１で構成される。図２の制御装置６において、比較判定部６１、駆動制御部６２および記憶部６３の各機能は、処理回路７１により実現される。 FIG. 3 is a hardware configuration diagram showing an example of the configuration of the control device 6 of FIG. When various functions of the control device 6 are executed by hardware, the control device 6 of FIG. 2 is composed of a processing circuit 71 as shown in FIG. In the control device 6 of FIG. 2, each function of the comparison determination unit 61, the drive control unit 62, and the storage unit 63 is realized by the processing circuit 71.
　各機能がハードウェアで実行される場合、処理回路７１は、例えば、単一回路、複合回路、プログラム化したプロセッサ、並列プログラム化したプロセッサ、ＡＳＩＣ（Ａｐｐｌｉｃａｔｉｏｎ　Ｓｐｅｃｉｆｉｃ　Ｉｎｔｅｇｒａｔｅｄ　Ｃｉｒｃｕｉｔ）、ＦＰＧＡ（Ｆｉｅｌｄ－Ｐｒｏｇｒａｍｍａｂｌｅ　Ｇａｔｅ　Ａｒｒａｙ）、またはこれらを組み合わせたものが該当する。制御装置６は、比較判定部６１、駆動制御部６２および記憶部６３の各部の機能それぞれを処理回路７１で実現してもよいし、各部の機能を１つの処理回路７１で実現してもよい。 When each function is executed by hardware, the processing circuit 71 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), or an FPGA (Field-Programmable Gate). Array), or a combination of these. In the control device 6, each of the functions of the comparison determination unit 61, the drive control unit 62, and the storage unit 63 may be realized by the processing circuit 71, or the functions of each part may be realized by one processing circuit 71. ..
　図４は、図２の制御装置６の構成の他の例を示すハードウェア構成図である。制御装置６の各種機能がソフトウェアで実行される場合、図２の制御装置６は、図４に示すように、プロセッサ８１およびメモリ８２で構成される。制御装置６において、比較判定部６１、駆動制御部６２および記憶部６３の各機能は、プロセッサ８１およびメモリ８２により実現される。 FIG. 4 is a hardware configuration diagram showing another example of the configuration of the control device 6 of FIG. When various functions of the control device 6 are executed by software, the control device 6 of FIG. 2 is composed of a processor 81 and a memory 82 as shown in FIG. In the control device 6, each function of the comparison determination unit 61, the drive control unit 62, and the storage unit 63 is realized by the processor 81 and the memory 82.
　各機能がソフトウェアで実行される場合、制御装置６において、比較判定部６１、駆動制御部６２および記憶部６３の機能は、ソフトウェア、ファームウェア、またはソフトウェアとファームウェアとの組み合わせにより実現される。ソフトウェアおよびファームウェアは、プログラムとして記述され、メモリ８２に格納される。プロセッサ８１は、メモリ８２に記憶されたプログラムを読み出して実行することにより、各部の機能を実現する。 When each function is executed by software, in the control device 6, the functions of the comparison determination unit 61, the drive control unit 62, and the storage unit 63 are realized by software, firmware, or a combination of software and firmware. The software and firmware are written as a program and stored in the memory 82. The processor 81 realizes the functions of each part by reading and executing the program stored in the memory 82.
　メモリ８２として、例えば、ＲＡＭ（Ｒａｎｄｏｍ　Ａｃｃｅｓｓ　Ｍｅｍｏｒｙ）、ＲＯＭ（Ｒｅａｄ　Ｏｎｌｙ　Ｍｅｍｏｒｙ）、フラッシュメモリ、ＥＰＲＯＭ（Ｅｒａｓａｂｌｅ　ａｎｄ　Ｐｒｏｇｒａｍｍａｂｌｅ　ＲＯＭ）およびＥＥＰＲＯＭ（Ｅｌｅｃｔｒｉｃａｌｌｙ　Ｅｒａｓａｂｌｅ　ａｎｄ　Ｐｒｏｇｒａｍｍａｂｌｅ　ＲＯＭ）等の不揮発性または揮発性の半導体メモリ等が用いられる。また、メモリ８２として、例えば、磁気ディスク、フレキシブルディスク、光ディスク、ＣＤ（Ｃｏｍｐａｃｔ　Ｄｉｓｃ）、ＭＤ（Ｍｉｎｉ　Ｄｉｓｃ）およびＤＶＤ（Ｄｉｇｉｔａｌ　Ｖｅｒｓａｔｉｌｅ　Ｄｉｓｃ）等の着脱可能な記録媒体が用いられてもよい。 As the memory 82, for example, RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable and Programmable ROM), EEPROM (Electrically Erasable, volatile ROM, etc.) Is used. Further, as the memory 82, for example, a removable recording medium such as a magnetic disk, a flexible disk, an optical disk, a CD (Compact Disc), an MD (Mini Disc), or a DVD (Digital Versaille Disc) may be used.
［圧縮機１の動作］
　次に、本実施の形態１に係る圧縮機１の動作について説明する。図５は、本実施の形態１に係る圧縮機１の圧縮原理を示す概略図である。図５では、紙面左側から順に、「吸入行程」、「圧縮行程」および「吐出行程」を示している。 [Operation of compressor 1]
Next, the operation of the compressor 1 according to the first embodiment will be described. FIG. 5 is a schematic view showing the compression principle of the compressor 1 according to the first embodiment. In FIG. 5, the “suction stroke”, the “compression stroke”, and the “discharge stroke” are shown in order from the left side of the paper.
　図５に示すように、圧縮機１において、インバータ５によりモータ１０が起動されると、スクリュー軸１１（図１参照）が回転するのに伴ってスクリューロータ１２が実線矢印の方向に回転する。このとき、スクリューロータ１２のスクリュー溝１２ａには、ゲートロータ１３の歯１３ａが噛み合っている。そのため、スクリューロータ１２が回転すると、ゲートロータ１３の歯１３ａがスクリュー溝１２ａ内を相対的に移動し、ゲートロータ１３は、細白抜き矢印の方向に回転する。これにより、圧縮室１４内では吸入行程、圧縮行程および吐出行程を一サイクルとして、このサイクルを繰り返すようになっている。ここでは、図５においてドットのハッチングで示した圧縮室１４に着目して各行程について説明する。 As shown in FIG. 5, when the motor 10 is started by the inverter 5 in the compressor 1, the screw rotor 12 rotates in the direction of the solid arrow as the screw shaft 11 (see FIG. 1) rotates. At this time, the teeth 13a of the gate rotor 13 are engaged with the screw groove 12a of the screw rotor 12. Therefore, when the screw rotor 12 rotates, the teeth 13a of the gate rotor 13 move relatively in the screw groove 12a, and the gate rotor 13 rotates in the direction of the thin white arrow. As a result, in the compression chamber 14, the suction stroke, the compression stroke, and the discharge stroke are set as one cycle, and this cycle is repeated. Here, each process will be described focusing on the compression chamber 14 shown by the hatching of dots in FIG.
　図５の左側の図は、吸入行程における圧縮室１４の状態を示している。スクリューロータ１２がモータ１０により駆動されて実線矢印の方向に回転すると、この回転に連動してゲートロータ１３の歯１３ａが順次吐出口側へ回転移動する。これにより、図５の中央の図に示すように、圧縮室１４の容積が縮小し、圧縮室１４内の冷媒ガスが圧縮される。 The figure on the left side of FIG. 5 shows the state of the compression chamber 14 in the suction stroke. When the screw rotor 12 is driven by the motor 10 and rotates in the direction of the solid arrow, the teeth 13a of the gate rotor 13 sequentially rotate and move toward the discharge port side in conjunction with this rotation. As a result, as shown in the central figure of FIG. 5, the volume of the compression chamber 14 is reduced, and the refrigerant gas in the compression chamber 14 is compressed.
　引き続きスクリューロータ１２が回転すると、図５の右側の図に示すように、圧縮室１４が吐出口１ｃに連通する。これにより、圧縮室１４内で圧縮された高圧の冷媒ガスが吐出口１ｃから高圧部１６へ吐出される。そして、再びスクリューロータ１２の背面で同様の圧縮が行われる。 When the screw rotor 12 continues to rotate, the compression chamber 14 communicates with the discharge port 1c as shown in the figure on the right side of FIG. As a result, the high-pressure refrigerant gas compressed in the compression chamber 14 is discharged from the discharge port 1c to the high-pressure portion 16. Then, the same compression is performed again on the back surface of the screw rotor 12.
　なお、ケーシング１ａ、ゲートロータ１３の歯１３ａおよびスクリューロータ１２等によって形成される圧縮室１４には、ゲートロータ１３およびスクリューロータ１２が回転するための図示しない微小空間が設けられている。この微小空間は、圧縮室１４内で圧縮された高圧の冷媒ガス、および圧縮室１４に給油された冷凍機油が低圧部１５へ漏れる流路となっている。 The compression chamber 14 formed by the casing 1a, the teeth 13a of the gate rotor 13, the screw rotor 12, and the like is provided with a minute space (not shown) for the gate rotor 13 and the screw rotor 12 to rotate. This minute space is a flow path through which the high-pressure refrigerant gas compressed in the compression chamber 14 and the refrigerating machine oil supplied to the compression chamber 14 leak to the low-pressure portion 15.
［回転制動制御および均圧制御］
　次に、制御装置６による回転制動制御について説明する。本実施の形態１では、圧縮機１の運転を停止させる際に、スクリューロータ１２の逆回転を防止または抑制するように、モータ１０の回転を制御する回転制動制御を行う。また、本実施の形態１では、このとき、連通流路２０を介して高圧部１６の冷媒を低圧部１５へ流入させる均圧制御を行う。以下、回転制動制御および均圧制御について、図６に示す具体例を参照して説明する。 [Rotary braking control and pressure equalization control]
Next, the rotation braking control by the control device 6 will be described. In the first embodiment, rotational braking control is performed to control the rotation of the motor 10 so as to prevent or suppress the reverse rotation of the screw rotor 12 when the operation of the compressor 1 is stopped. Further, in the first embodiment, at this time, pressure equalization control is performed so that the refrigerant of the high pressure portion 16 flows into the low pressure portion 15 via the communication flow path 20. Hereinafter, rotational braking control and pressure equalization control will be described with reference to a specific example shown in FIG.
　図６は、本実施の形態１における回転制動制御および均圧制御について説明するための概略図である。図６において、グラフの縦軸はインバータ５からの指令運転周波数を示し、横軸は時間を示す。また、図６では、グラフに示される時間に対応する回転制動制御および流量調整弁２１の状態を示す。 FIG. 6 is a schematic diagram for explaining rotational braking control and pressure equalization control according to the first embodiment. In FIG. 6, the vertical axis of the graph indicates the command operation frequency from the inverter 5, and the horizontal axis indicates time. Further, FIG. 6 shows the state of the rotary braking control and the flow rate adjusting valve 21 corresponding to the time shown in the graph.
　時刻Ｔ０において、圧縮機１が運転周波数Ｆ２で運転しているものとする。時刻Ｔ１において、制御装置６が外部から圧縮機１を停止させるための停止指令を受信すると、駆動制御部６２は、圧縮機１に対する停止制御を行う。そして、駆動制御部６２は、圧縮機１の運転周波数をＦ２から、Ｆ２よりも低い周波数Ｆ１に低下させるように、インバータ５に対して指令を出力する。インバータ５は、駆動制御部６２からの指令に基づき、圧縮機１の運転周波数をＦ２からＦ１に低下させる。 At time T 0, it is assumed that the compressor 1 is driven at a driving frequency F 2. At time T 1, the control device 6 receives the stop command for stopping the compressor 1 from the outside, the drive control unit 62 performs stop control for the compressor 1. Then, the drive control unit 62 outputs a command to the inverter 5 so as to lower the operating frequency of the compressor 1 from F 2 to a frequency F 1 lower than F 2 . The inverter 5 lowers the operating frequency of the compressor 1 from F 2 to F 1 based on a command from the drive control unit 62.
　次に、時刻Ｔ２において、運転周波数がＦ１となると、制御装置６は、回転制動制御を行う。駆動制御部６２は、ステータ１０ａに予め設定した直流電圧を印加するように、インバータ５に対して指令を出力する。インバータ５は、ステータ１０ａに直流電圧を印加する。これにより、モータ１０にトルクが発生し、モータロータ１０ｂを回転させようとする力を受けても、モータロータ１０ｂの回転が防止または抑制される回転制動制御が行われる。 Next, at time T 2 , when the operating frequency becomes F 1 , the control device 6 performs rotational braking control. The drive control unit 62 outputs a command to the inverter 5 so as to apply a preset DC voltage to the stator 10a. The inverter 5 applies a DC voltage to the stator 10a. As a result, even if torque is generated in the motor 10 and a force is applied to rotate the motor rotor 10b, rotation braking control is performed in which the rotation of the motor rotor 10b is prevented or suppressed.
　また、回転制動制御が行われると、制御装置６は、同時に均圧制御を行う。駆動制御部６２は、圧縮機１の流量調整弁２１を開くように制御する。これにより、圧縮機１の高圧部１６内の冷媒が連通流路２０を介して低圧部１５へ流入し、高圧部１６と低圧部１５との圧力差が減少し、高圧部１６および低圧部１５内の圧力の均一化が進む。 Further, when the rotational braking control is performed, the control device 6 simultaneously performs pressure equalization control. The drive control unit 62 controls the flow rate adjusting valve 21 of the compressor 1 to open. As a result, the refrigerant in the high-pressure section 16 of the compressor 1 flows into the low-pressure section 15 via the communication flow path 20, the pressure difference between the high-pressure section 16 and the low-pressure section 15 is reduced, and the high-pressure section 16 and the low-pressure section 15 are reduced. The pressure inside becomes uniform.
　時刻Ｔ３において、設定回転制動時間が経過すると、制御装置６は、回転制動制御を終了する。また、同時に設定均圧時間が経過するため、駆動制御部６２は、圧縮機１の流量調整弁２１を閉じるように制御する。これにより、均圧制御が終了する。 At time T 3, when the elapse of the set rotation braking time, the control unit 6 ends the rotational braking control. Further, since the set pressure equalizing time elapses at the same time, the drive control unit 62 controls to close the flow rate adjusting valve 21 of the compressor 1. As a result, the pressure equalization control is completed.
　このように、回転制動制御は、記憶部６３に記憶された設定回転制動時間だけ行われる。また、均圧制御は、記憶部６３に記憶された設定均圧時間だけ行われる。このとき、設定回転制動時間は、設定均圧時間に含まれるように設定される。したがって、均圧制御は、回転制動制御の期間を含む期間に行われる。 In this way, the rotation braking control is performed only for the set rotation braking time stored in the storage unit 63. Further, the pressure equalization control is performed only for the set pressure equalization time stored in the storage unit 63. At this time, the set rotation braking time is set to be included in the set pressure equalization time. Therefore, the pressure equalizing control is performed during the period including the period of the rotational braking control.
　特に、本実施の形態１においては、設定回転制動時間および設定均圧時間が同一の時間に設定される。すなわち、本実施の形態１では、回転制動制御の開始と同時に均圧制御が開始され、回転制動制御の終了と同時に均圧制御が終了する。 In particular, in the first embodiment, the set rotation braking time and the set pressure equalizing time are set to the same time. That is, in the first embodiment, the pressure equalizing control is started at the same time as the rotation braking control is started, and the pressure equalizing control is finished at the same time as the rotation braking control is finished.
　図７は、本実施の形態１における回転制動制御および均圧制御の処理の流れの一例を示すフローチャートである。まず、ステップＳ１において、制御装置６は、外部から圧縮機１の停止指令を受信したか否かを判断する。圧縮機１の停止指令を受信した場合（ステップＳ１：Ｙｅｓ）には、処理がステップＳ２に移行する。一方、停止指令を受信していない場合（ステップＳ１：Ｎｏ）には、処理がステップＳ１に戻り、停止指令を受信するまでステップＳ１の処理が繰り返される。 FIG. 7 is a flowchart showing an example of the processing flow of the rotation braking control and the pressure equalizing control in the first embodiment. First, in step S1, the control device 6 determines whether or not a stop command for the compressor 1 has been received from the outside. When the stop command of the compressor 1 is received (step S1: Yes), the process proceeds to step S2. On the other hand, when the stop command is not received (step S1: No), the process returns to step S1, and the process of step S1 is repeated until the stop command is received.
　ステップＳ２において、駆動制御部６２は、圧縮機１の運転周波数を低下させるように、インバータ５を制御する。次に、ステップＳ３において、比較判定部６１は、圧縮機１の運転周波数がＦ１であるか否かを判定する。 In step S2, the drive control unit 62 controls the inverter 5 so as to lower the operating frequency of the compressor 1. Next, in step S3, the comparison and determination section 61, the operating frequency of the compressor 1 is determined whether the F 1.
　圧縮機１の運転周波数がＦ１である場合（ステップＳ３：Ｙｅｓ）、制御装置６は、ステップＳ４において回転制動制御を開始する。そして、ステップＳ５において、駆動制御部６２は、流量調整弁２１を開くように制御する。一方、圧縮機１の運転周波数がＦ１でない場合（ステップＳ３：Ｎｏ）には、処理がステップＳ３に戻り、運転周波数がＦ１になるまでステップＳ３の処理が繰り返される。 When the operating frequency of the compressor 1 is F 1 (step S3: Yes), the control device 6 starts the rotation braking control in step S4. Then, in step S5, the drive control unit 62 controls to open the flow rate adjusting valve 21. On the other hand, if the operation frequency of the compressor 1 is not F 1: (the step S3 No), the process returns to step S3, the operating frequency is step S3 is repeated until the F 1.
　ステップＳ６において、比較判定部６１は、回転制動制御および均圧制御が開始されてから設定回転制動時間および設定均圧時間が経過したか否かを判定する。設定回転制動時間および設定均圧時間が経過したと判断した場合（ステップＳ６：Ｙｅｓ）、制御装置６は、ステップＳ７において、回転制動制御を終了する。また、制御装置６は、ステップＳ８において、流量調整弁２１を閉じるように制御し、均圧制御を終了する。一方、設定回転制動時間および設定均圧時間が経過していないと判断した場合（ステップＳ６：Ｎｏ）には、処理がステップＳ６に戻り、設定回転制動時間および設定均圧時間が経過するまで、回転制動制御および均圧制御が継続される。 In step S6, the comparison determination unit 61 determines whether or not the set rotation braking time and the set pressure equalizing time have elapsed since the rotation braking control and the pressure equalizing control were started. When it is determined that the set rotation braking time and the set pressure equalizing time have elapsed (step S6: Yes), the control device 6 ends the rotation braking control in step S7. Further, in step S8, the control device 6 controls so as to close the flow rate adjusting valve 21 and ends the pressure equalization control. On the other hand, when it is determined that the set rotation braking time and the set pressure equalizing time have not elapsed (step S6: No), the process returns to step S6 until the set rotation braking time and the set pressure equalizing time elapse. Rotational braking control and pressure equalization control are continued.
　以上のように、本実施の形態１に係る冷凍装置１００では、圧縮機１の運転が停止した際に、インバータ５を制御して回転制動制御が行われるとともに、流量調整弁２１を開いて高圧部１６と低圧部１５とを均圧する均圧制御が行われる。特に、本実施の形態１では、回転制動制御と同一期間中に均圧制御が行われる。これにより、回転制動制御中に流量調整弁２１が開いて高圧部１６から低圧部１５に冷媒が流れ、高圧部１６と低圧部１５とが均圧されるため、高圧部１６および低圧部１５の均圧時間を短縮することができる。 As described above, in the refrigerating apparatus 100 according to the first embodiment, when the operation of the compressor 1 is stopped, the inverter 5 is controlled to perform rotational braking control, and the flow rate adjusting valve 21 is opened to perform high pressure. Pressure equalization control is performed to equalize the pressure between the unit 16 and the low pressure unit 15. In particular, in the first embodiment, the pressure equalization control is performed during the same period as the rotational braking control. As a result, the flow rate adjusting valve 21 opens during the rotary braking control, the refrigerant flows from the high pressure portion 16 to the low pressure portion 15, and the high pressure portion 16 and the low pressure portion 15 are equalized, so that the high pressure portion 16 and the low pressure portion 15 The pressure equalization time can be shortened.
　また、均圧時間が短縮されることにより、回転制動制御が終了した後のスクリューロータ１２の逆回転が防止または抑制されるため、ゲートロータ１３の損傷または摩耗を抑制することができる。さらに、均圧時間が短縮されることにより、給油穴を介した高圧部１６から低圧部１５に対する過度の油の流出が抑制されるため、次に圧縮機１を起動させる際の、液圧縮（油圧縮）によるゲートロータ１３破損等を防止することができる。 Further, since the pressure equalizing time is shortened, the reverse rotation of the screw rotor 12 after the rotation braking control is completed is prevented or suppressed, so that damage or wear of the gate rotor 13 can be suppressed. Further, since the pressure equalizing time is shortened, excessive oil outflow from the high pressure portion 16 to the low pressure portion 15 through the refueling hole is suppressed, so that the liquid compression (the next time the compressor 1 is started) is performed. It is possible to prevent damage to the gate rotor 13 due to oil compression).
　冷凍装置１００において、制御装置６は、インバータ５を制御して、圧縮機１の運転周波数が運転時の周波数Ｆ２よりも低い周波数Ｆ１となった場合に、回転制動制御を行う。これにより、圧縮機１を運転状態から突然停止状態とすることによる圧縮機１の損傷等を防止することができる。 In the refrigerating device 100, the control device 6 controls the inverter 5 to perform rotational braking control when the operating frequency of the compressor 1 becomes a frequency F 1 lower than the operating frequency F 2 . This makes it possible to prevent damage to the compressor 1 due to suddenly stopping the compressor 1 from the operating state.
　冷凍装置１００において、連通流路２０は、圧縮機１のケーシング１ａの外部に設けられてもよいし、ケーシング１ａの内部に設けられてもよい。 In the refrigerating apparatus 100, the communication flow path 20 may be provided outside the casing 1a of the compressor 1 or may be provided inside the casing 1a.
実施の形態２．
　次に、本実施の形態２について説明する。本実施の形態２では、均圧制御が、回転制動制御が終了した後も継続される点で、実施の形態１と相違する。なお、本実施の形態２において、実施の形態１と共通する部分には同一の符号を付し、詳細な説明を省略する。 Embodiment 2.
Next, the second embodiment will be described. The second embodiment is different from the first embodiment in that the pressure equalizing control is continued even after the rotational braking control is completed. In the second embodiment, the same reference numerals are given to the parts common to the first embodiment, and detailed description thereof will be omitted.
　本実施の形態２において、均圧制御は、回転制動制御と同時に行われるが、回転制動制御が終了した後も継続される。すなわち、本実施の形態２において、設定均圧時間は、設定回転制動時間よりも長くなるように設定される。 In the second embodiment, the pressure equalizing control is performed at the same time as the rotational braking control, but is continued even after the rotational braking control is completed. That is, in the second embodiment, the set pressure equalizing time is set to be longer than the set rotation braking time.
［回転制動制御および均圧制御］
　図８は、本実施の形態２における回転制動制御および均圧制御について説明するための概略図である。図８において、グラフの縦軸はインバータ５からの指令運転周波数を示し、横軸は時間を示す。また、図８では、グラフに示される時間に対応する回転制動制御および流量調整弁２１の状態を示す。 [Rotary braking control and pressure equalization control]
FIG. 8 is a schematic view for explaining rotational braking control and pressure equalization control according to the second embodiment. In FIG. 8, the vertical axis of the graph indicates the command operation frequency from the inverter 5, and the horizontal axis indicates time. Further, FIG. 8 shows the state of the rotary braking control and the flow rate adjusting valve 21 corresponding to the time shown in the graph.
　時刻Ｔ０において、圧縮機１が運転周波数Ｆ２で運転しているものとする。時刻Ｔ１において、制御装置６が外部から圧縮機１の停止指令を受信すると、駆動制御部６２は、圧縮機１に対する停止制御を行う。そして、駆動制御部６２は、圧縮機１の運転周波数をＦ２からＦ１に低下させるように、インバータ５に対して指令を出力する。インバータ５は、駆動制御部６２からの指令に基づき、圧縮機１の運転周波数をＦ２からＦ１に低下させる。 At time T 0, it is assumed that the compressor 1 is driven at a driving frequency F 2. At time T 1, the control device 6 receives the stop command compressor 1 from the outside, the drive control unit 62 performs stop control for the compressor 1. Then, the drive control unit 62 outputs a command to the inverter 5 so as to reduce the operating frequency of the compressor 1 from F 2 to F 1 . The inverter 5 lowers the operating frequency of the compressor 1 from F 2 to F 1 based on a command from the drive control unit 62.
　次に、時刻Ｔ２において、運転周波数がＦ１となると、制御装置６は、回転制動制御を行う。駆動制御部６２は、ステータ１０ａに予め設定した直流電圧を印加するように、インバータ５に対して指令を出力する。これにより、回転制動制御が行われる。また、回転制動制御が行われると、制御装置６は、均圧制御を行う。駆動制御部６２は、圧縮機１の流量調整弁２１を開くように制御する。 Next, at time T 2 , when the operating frequency becomes F 1 , the control device 6 performs rotational braking control. The drive control unit 62 outputs a command to the inverter 5 so as to apply a preset DC voltage to the stator 10a. As a result, rotational braking control is performed. Further, when the rotational braking control is performed, the control device 6 performs pressure equalization control. The drive control unit 62 controls the flow rate adjusting valve 21 of the compressor 1 to open.
　時刻Ｔ３において、設定回転制動時間が経過すると、制御装置６は、回転制動制御を終了する。一方、設定均圧時間は、設定回転制動時間よりも長いため、圧縮機１の流量調整弁２１は、開状態を維持し、均圧制御が継続される。 At time T 3, when the elapse of the set rotation braking time, the control unit 6 ends the rotational braking control. On the other hand, since the set pressure equalization time is longer than the set rotation braking time, the flow rate adjusting valve 21 of the compressor 1 is maintained in the open state, and the pressure equalization control is continued.
　そして、時刻Ｔ４において、設定均圧時間が経過すると、駆動制御部６２は、圧縮機１の流量調整弁２１を閉じるように制御する。これにより、均圧制御が終了する。 Then, at time T 4, when the elapse of between setting equalizing pressure time, the drive control unit 62 controls so as to close the flow control valve 21 of the compressor 1. As a result, the pressure equalization control is completed.
　このように、本実施の形態２においては、設定均圧時間が設定回転制動時間よりも長く設定される。すなわち、本実施の形態２では、均圧制御は、回転制動制御が行われると同時に行われるため、回転制動制御が終了した後も継続して行われる。 As described above, in the second embodiment, the set pressure equalizing time is set longer than the set rotation braking time. That is, in the second embodiment, since the pressure equalizing control is performed at the same time as the rotational braking control is performed, it is continuously performed even after the rotational braking control is completed.
　図９は、本実施の形態２における回転制動制御および均圧制御の処理の流れの一例を示すフローチャートである。ステップＳ１からステップＳ５までの処理は、実施の形態１と同様であるため、説明を省略する。 FIG. 9 is a flowchart showing an example of the processing flow of the rotation braking control and the pressure equalizing control in the second embodiment. Since the processes from step S1 to step S5 are the same as those in the first embodiment, the description thereof will be omitted.
　ステップＳ１６において、比較判定部６１は、回転制動制御が開始されてから設定回転制動時間が経過したか否かを判定する。設定回転制動時間が経過したと判断した場合（ステップＳ１６：Ｙｅｓ）、制御装置６は、ステップＳ１７において、回転制動制御を終了する。一方、設定回転制動時間が経過していないと判断した場合（ステップＳ１６：Ｎｏ）には、処理がステップＳ１６に戻り、設定回転制動時間が経過するまで、回転制動制御が継続される。 In step S16, the comparison determination unit 61 determines whether or not the set rotation braking time has elapsed since the rotation braking control was started. When it is determined that the set rotation braking time has elapsed (step S16: Yes), the control device 6 ends the rotation braking control in step S17. On the other hand, when it is determined that the set rotation braking time has not elapsed (step S16: No), the process returns to step S16, and the rotation braking control is continued until the set rotation braking time elapses.
　ステップＳ１８において、比較判定部６１は、均圧制御が開始されてから設定均圧時間が経過したか否かを判定する。設定均圧時間が経過したと判断した場合（ステップＳ１８：Ｙｅｓ）、制御装置６は、ステップＳ１９において、均圧制御を終了する。一方、設定均圧時間が経過していないと判断した場合（ステップＳ１８：Ｎｏ）には、処理がステップＳ１８に戻り、設定均圧時間が経過するまで、均圧制御が継続される。 In step S18, the comparison determination unit 61 determines whether or not the set pressure equalization time has elapsed since the pressure equalization control was started. When it is determined that the set pressure equalization time has elapsed (step S18: Yes), the control device 6 ends the pressure equalization control in step S19. On the other hand, when it is determined that the set pressure equalization time has not elapsed (step S18: No), the process returns to step S18, and the pressure equalization control is continued until the set pressure equalization time elapses.
　以上のように、本実施の形態２に係る冷凍装置１００において、均圧制御は、回転制動制御が終了しても継続される。これにより、回転制動制御が終了した後に、高圧部１６と低圧部１５との均圧が十分でない場合でも、継続して均圧されるため、均圧時間をより短縮することができる。 As described above, in the refrigerating apparatus 100 according to the second embodiment, the pressure equalizing control is continued even after the rotational braking control is completed. As a result, even if the pressure equalization between the high pressure portion 16 and the low pressure portion 15 is not sufficient after the rotation braking control is completed, the pressure equalization is continued, so that the pressure equalization time can be further shortened.
実施の形態３．
　次に、本実施の形態３について説明する。本実施の形態３では、均圧制御が、回転制動制御が開始される前から行われる点で、実施の形態１と相違する。なお、本実施の形態３において、実施の形態１および２と共通する部分には同一の符号を付し、詳細な説明を省略する。 Embodiment 3.
Next, the third embodiment will be described. The third embodiment is different from the first embodiment in that the pressure equalizing control is performed before the rotational braking control is started. In the third embodiment, the parts common to the first and second embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.
　本実施の形態３において、均圧制御は、回転制動制御が開始される前から行われ、回転制動制御の終了と同時に終了する。すなわち、本実施の形態３において、設定均圧時間は、設定回転制動時間よりも長くなるように設定される。また、本実施の形態３では、均圧制御の開始時間を示す設定均圧開始時間が予め設定され、この設定均圧開始時間は、回転制動制御の開始前となる時間に設定される。 In the third embodiment, the pressure equalizing control is performed before the rotation braking control is started, and ends at the same time as the rotation braking control ends. That is, in the third embodiment, the set pressure equalizing time is set to be longer than the set rotation braking time. Further, in the third embodiment, the set pressure equalization start time indicating the start time of the pressure equalization control is set in advance, and the set pressure equalization start time is set to a time before the start of the rotational braking control.
　設定均圧開始時間は、制御装置６の記憶部６３に予め記憶されている。設定均圧開始時間は、回転制動制御の開始前であれば任意の時間に設定される。なお、設定均圧開始時間は、圧縮機１の停止指令を受信する前のタイミングでもよいし、停止指令を受信した後のタイミングでもよい。 The set pressure equalization start time is stored in advance in the storage unit 63 of the control device 6. The set pressure equalization start time is set to an arbitrary time before the start of the rotary braking control. The set pressure equalization start time may be the timing before receiving the stop command of the compressor 1 or the timing after receiving the stop command.
［回転制動制御および均圧制御］
　図１０は、本実施の形態３における回転制動制御および均圧制御について説明するための概略図である。図１０において、グラフの縦軸はインバータ５からの指令運転周波数を示し、横軸は時間を示す。また、図１０では、グラフに示される時間に対応する回転制動制御および流量調整弁２１の状態を示す。さらに、図１０の例は、設定均圧開始時間が圧縮機１の停止指令を受信する前のタイミングに設定されている場合を示す。 [Rotary braking control and pressure equalization control]
FIG. 10 is a schematic view for explaining rotational braking control and pressure equalization control according to the third embodiment. In FIG. 10, the vertical axis of the graph indicates the command operation frequency from the inverter 5, and the horizontal axis indicates time. Further, FIG. 10 shows the state of the rotary braking control and the flow rate adjusting valve 21 corresponding to the time shown in the graph. Further, the example of FIG. 10 shows a case where the set pressure equalization start time is set to the timing before receiving the stop command of the compressor 1.
　時刻Ｔ０において、圧縮機１が運転周波数Ｆ２で運転しているものとする。時刻Ｔ１Ａにおいて、設定均圧開始時間になると、制御装置６は、均圧制御を行う。駆動制御部６２は、圧縮機１の流量調整弁２１を開くように制御する。 At time T 0, it is assumed that the compressor 1 is driven at a driving frequency F 2. At time T 1A, At the set pressure equalizing start time, the control unit 6 performs control pressure equalization. The drive control unit 62 controls the flow rate adjusting valve 21 of the compressor 1 to open.
　時刻Ｔ１において、制御装置６が外部から圧縮機１の停止指令を受信すると、駆動制御部６２は、圧縮機１に対する停止制御を行う。そして、駆動制御部６２は、圧縮機１の運転周波数をＦ２からＦ１に低下させるように、インバータ５に対して指令を出力する。インバータ５は、駆動制御部６２からの指令に基づき、圧縮機１の運転周波数をＦ２からＦ１に低下させる。 At time T 1, the control device 6 receives the stop command compressor 1 from the outside, the drive control unit 62 performs stop control for the compressor 1. Then, the drive control unit 62 outputs a command to the inverter 5 so as to reduce the operating frequency of the compressor 1 from F 2 to F 1 . The inverter 5 lowers the operating frequency of the compressor 1 from F 2 to F 1 based on a command from the drive control unit 62.
　次に、時刻Ｔ２において、運転周波数がＦ１となると、制御装置６は、回転制動制御を行う。駆動制御部６２は、ステータ１０ａに予め設定した直流電圧を印加するように、インバータ５に対して指令を出力する。これにより、回転制動制御が行われる。 Next, at time T 2 , when the operating frequency becomes F 1 , the control device 6 performs rotational braking control. The drive control unit 62 outputs a command to the inverter 5 so as to apply a preset DC voltage to the stator 10a. As a result, rotational braking control is performed.
　時刻Ｔ３において、設定回転制動時間が経過すると、制御装置６は、回転制動制御を終了する。また、同時に設定均圧時間が経過するため、駆動制御部６２は、圧縮機１の流量調整弁２１を閉じるように制御する。これにより、均圧制御が終了する。 At time T 3, when the elapse of the set rotation braking time, the control unit 6 ends the rotational braking control. Further, since the set pressure equalizing time elapses at the same time, the drive control unit 62 controls to close the flow rate adjusting valve 21 of the compressor 1. As a result, the pressure equalization control is completed.
　このように、本実施の形態３においては、設定均圧時間が設定回転制動時間よりも長く設定される。また、設定均圧開始時間が回転制動制御の開始前に設定される。すなわち、本実施の形態３では、均圧制御は、回転制動制御が開始される前に行われる。 As described above, in the third embodiment, the set pressure equalizing time is set longer than the set rotation braking time. Further, the set pressure equalization start time is set before the start of the rotary braking control. That is, in the third embodiment, the pressure equalizing control is performed before the rotational braking control is started.
　図１１は、本実施の形態３における回転制動制御および均圧制御の処理の流れの一例を示すフローチャートである。なお、図１１の例は、設定均圧開始時間が圧縮機１の停止指令よりも前に設定されている場合を示す。 FIG. 11 is a flowchart showing an example of the processing flow of the rotation braking control and the pressure equalizing control in the third embodiment. The example of FIG. 11 shows a case where the set pressure equalization start time is set before the stop command of the compressor 1.
　まず、ステップＳ２１において、比較判定部６１は、記憶部６３に記憶された設定均圧開始時間であるか否かを判断する。設定均圧開始時間である場合（ステップＳ２１：Ｙｅｓ）、駆動制御部６２は、ステップＳ２２において、流量調整弁２１を開くように制御する。一方、設定均圧開始時間でない場合（ステップＳ２１：Ｎｏ）には、処理がステップＳ２１に戻り、設定均圧開始時間になるまでステップＳ２１の処理が繰り返される。 First, in step S21, the comparison determination unit 61 determines whether or not the set pressure equalization start time stored in the storage unit 63 is reached. When the set pressure equalization start time is reached (step S21: Yes), the drive control unit 62 controls in step S22 to open the flow rate adjusting valve 21. On the other hand, when it is not the set pressure equalization start time (step S21: No), the process returns to step S21, and the process of step S21 is repeated until the set pressure equalization start time is reached.
　ステップＳ２３において、制御装置６は、外部から圧縮機１の停止指令を受信したか否かを判断する。圧縮機１の停止指令を受信した場合（ステップＳ２３：Ｙｅｓ）、駆動制御部６２は、ステップＳ２４において、圧縮機１の運転周波数を低下させるように、インバータ５を制御する。一方、停止指令を受信していない場合（ステップＳ２３：Ｎｏ）には、処理がステップＳ２３に戻り、停止指令を受信するまでステップＳ２３の処理が繰り返される。 In step S23, the control device 6 determines whether or not a stop command for the compressor 1 has been received from the outside. When the stop command of the compressor 1 is received (step S23: Yes), the drive control unit 62 controls the inverter 5 so as to lower the operating frequency of the compressor 1 in step S24. On the other hand, when the stop command is not received (step S23: No), the process returns to step S23, and the process of step S23 is repeated until the stop command is received.
　次に、ステップＳ２５において、比較判定部６１は、圧縮機１の運転周波数がＦ１であるか否かを判定する。圧縮機１の運転周波数がＦ１である場合（ステップＳ２５：Ｙｅｓ）、制御装置６は、ステップＳ２６において回転制動制御を開始する。一方、圧縮機１の運転周波数がＦ１でない場合（ステップＳ２５：Ｎｏ）には、処理がステップＳ２５に戻り、運転周波数がＦ１になるまでステップＳ２５の処理が繰り返される。 Next, in step S25, the comparison and determination unit 61, the operating frequency of the compressor 1 is determined whether the F 1. When the operating frequency of the compressor 1 is F 1 (step S25: Yes), the control device 6 starts the rotation braking control in step S26. On the other hand, if the operation frequency of the compressor 1 is not F 1 (step S25: No), the process returns to step S25, the operating frequency is step S25 is repeated until the F 1.
　ステップＳ２７において、比較判定部６１は、回転制動制御および均圧制御が開始されてから設定回転制動時間および設定均圧時間がそれぞれ経過したか否かを判定する。設定回転制動時間および設定均圧時間が経過したと判断した場合（ステップＳ２７：Ｙｅｓ）、制御装置６は、ステップＳ２８において、回転制動制御を終了する。また、制御装置６は、ステップＳ２９において、流量調整弁２１を閉じるように制御し、均圧制御を終了する。一方、設定回転制動時間および設定均圧時間が経過していないと判断した場合（ステップＳ２７：Ｎｏ）には、処理がステップＳ２７に戻り、設定回転制動時間および設定均圧時間が経過するまで、回転制動制御および均圧制御が継続される。 In step S27, the comparison determination unit 61 determines whether or not the set rotation braking time and the set pressure equalizing time have elapsed since the rotation braking control and the pressure equalizing control were started. When it is determined that the set rotation braking time and the set pressure equalizing time have elapsed (step S27: Yes), the control device 6 ends the rotation braking control in step S28. Further, in step S29, the control device 6 controls to close the flow rate adjusting valve 21 and ends the pressure equalization control. On the other hand, when it is determined that the set rotation braking time and the set pressure equalizing time have not elapsed (step S27: No), the process returns to step S27 until the set rotation braking time and the set pressure equalizing time elapse. Rotational braking control and pressure equalization control are continued.
　以上のように、本実施の形態３に係る冷凍装置１００において、均圧制御は、回転制動制御が開始される前に開始される。これにより、回転制動制御が終了した際の、高圧部１６と低圧部１５との差圧が小さくなるため、高圧部１６と低圧部１５との均圧時間をより短縮することができる。 As described above, in the refrigerating apparatus 100 according to the third embodiment, the pressure equalizing control is started before the rotational braking control is started. As a result, the differential pressure between the high-pressure portion 16 and the low-pressure portion 15 when the rotational braking control is completed becomes small, so that the pressure equalization time between the high-pressure portion 16 and the low-pressure portion 15 can be further shortened.
　また、回転制動制御が開始される際の高圧部１６と低圧部１５との差圧が小さくなるので、スクリューロータ１２の逆回転力が抑制される。これにより、回転制動制御の際のインバータ５からステータ１０ａに流れる直流電流を小さくすることができる。そのため、インバータ５に対して過大な電流が流れることを抑制できるので、インバータ５の破損を抑制することができる。 Further, since the differential pressure between the high pressure portion 16 and the low pressure portion 15 when the rotational braking control is started becomes small, the reverse rotational force of the screw rotor 12 is suppressed. As a result, the direct current flowing from the inverter 5 to the stator 10a during rotational braking control can be reduced. Therefore, it is possible to suppress the flow of an excessive current with respect to the inverter 5, so that damage to the inverter 5 can be suppressed.
実施の形態４．
　次に、本実施の形態４について説明する。本実施の形態４は、実施の形態２および３を組み合わせたものである。すなわち、本実施の形態４では、均圧制御が、回転制動制御が開始される前から行われ、回転制動制御が終了した後も継続される。なお、本実施の形態４において、実施の形態１～３と共通する部分には同一の符号を付し、詳細な説明を省略する。 Embodiment 4.
Next, the fourth embodiment will be described. The fourth embodiment is a combination of the second and third embodiments. That is, in the fourth embodiment, the pressure equalizing control is performed before the rotational braking control is started, and is continued even after the rotational braking control is completed. In the fourth embodiment, the parts common to the first to third embodiments are designated by the same reference numerals, and detailed description thereof will be omitted.
　本実施の形態４において、均圧制御は、回転制動制御が開始される前から行われ、回転制動制御が終了した後も継続される。すなわち、本実施の形態４において、設定均圧時間は、設定回転制動時間よりも長くなるように設定される。また、設定均圧開始時間は、回転制動制御の開始前に設定される。なお、設定均圧開始時間は、実施の形態３と同様に、圧縮機１の停止指令との関係は問わない。 In the fourth embodiment, the pressure equalizing control is performed before the rotation braking control is started, and is continued even after the rotation braking control is finished. That is, in the fourth embodiment, the set pressure equalizing time is set to be longer than the set rotation braking time. Further, the set pressure equalization start time is set before the start of the rotational braking control. The set pressure equalization start time does not matter whether it is related to the stop command of the compressor 1 as in the third embodiment.
［回転制動制御および均圧制御］
　図１２は、本実施の形態４における回転制動制御および均圧制御について説明するための概略図である。図１２において、グラフの縦軸はインバータ５からの指令運転周波数を示し、横軸は時間を示す。また、図１２では、グラフに示される時間に対応する回転制動制御および流量調整弁２１の状態を示す。 [Rotary braking control and pressure equalization control]
FIG. 12 is a schematic view for explaining rotational braking control and pressure equalization control according to the fourth embodiment. In FIG. 12, the vertical axis of the graph indicates the command operation frequency from the inverter 5, and the horizontal axis indicates time. Further, FIG. 12 shows the state of the rotary braking control and the flow rate adjusting valve 21 corresponding to the time shown in the graph.
　時刻Ｔ０において、圧縮機１が運転周波数Ｆ２で運転しているものとする。時刻Ｔ１Ａにおいて、設定均圧開始時間になると、制御装置６は、均圧制御を行う。駆動制御部６２は、圧縮機１の流量調整弁２１を開くように制御する。 At time T 0, it is assumed that the compressor 1 is driven at a driving frequency F 2. At time T 1A, At the set pressure equalizing start time, the control unit 6 performs control pressure equalization. The drive control unit 62 controls the flow rate adjusting valve 21 of the compressor 1 to open.
　時刻Ｔ１において、制御装置６が外部から圧縮機１の停止指令を受信すると、駆動制御部６２は、圧縮機１に対する停止制御を行う。そして、駆動制御部６２は、圧縮機１の運転周波数をＦ２からＦ１に低下させるように、インバータ５に対して指令を出力する。インバータ５は、駆動制御部６２からの指令に基づき、圧縮機１の運転周波数をＦ２からＦ１に低下させる。 At time T 1, the control device 6 receives the stop command compressor 1 from the outside, the drive control unit 62 performs stop control for the compressor 1. Then, the drive control unit 62 outputs a command to the inverter 5 so as to reduce the operating frequency of the compressor 1 from F 2 to F 1 . The inverter 5 lowers the operating frequency of the compressor 1 from F 2 to F 1 based on a command from the drive control unit 62.
　次に、時刻Ｔ２において、運転周波数がＦ１となると、制御装置６は、回転制動制御を行う。駆動制御部６２は、ステータ１０ａに予め設定した直流電圧を印加するように、インバータ５に対して指令を出力する。これにより、回転制動制御が行われる。 Next, at time T 2 , when the operating frequency becomes F 1 , the control device 6 performs rotational braking control. The drive control unit 62 outputs a command to the inverter 5 so as to apply a preset DC voltage to the stator 10a. As a result, rotational braking control is performed.
　時刻Ｔ３において、設定回転制動時間が経過すると、制御装置６は、回転制動制御を終了する。一方、設定均圧時間は、設定回転制動時間よりも長いため、圧縮機１の流量調整弁２１は、開状態を維持し、均圧制御が継続される。 At time T 3, when the elapse of the set rotation braking time, the control unit 6 ends the rotational braking control. On the other hand, since the set pressure equalization time is longer than the set rotation braking time, the flow rate adjusting valve 21 of the compressor 1 is maintained in the open state, and the pressure equalization control is continued.
　そして、時刻Ｔ４において、設定均圧時間が経過すると、駆動制御部６２は、圧縮機１の流量調整弁２１を閉じるように制御する。これにより、均圧制御が終了する。 Then, at time T 4, when the elapse of between setting equalizing pressure time, the drive control unit 62 controls so as to close the flow control valve 21 of the compressor 1. As a result, the pressure equalization control is completed.
　このように、本実施の形態４においては、設定均圧時間が設定回転制動時間よりも長く設定される。また、設定均圧開始時間が回転制動制御の開始前に設定される。すなわち、本実施の形態４では、均圧制御は、回転制動制御が開始される前に行われ、回転制動制御が終了した後も継続して行われる。 As described above, in the fourth embodiment, the set pressure equalizing time is set longer than the set rotation braking time. Further, the set pressure equalization start time is set before the start of the rotary braking control. That is, in the fourth embodiment, the pressure equalizing control is performed before the rotational braking control is started, and is continuously performed even after the rotational braking control is completed.
　図１３は、本実施の形態４における回転制動制御および均圧制御の処理の流れの一例を示すフローチャートである。なお、図１３の例は、設定均圧開始時間が圧縮機１の停止指令よりも前に設定されている場合を示す。 FIG. 13 is a flowchart showing an example of the processing flow of the rotation braking control and the pressure equalizing control in the fourth embodiment. The example of FIG. 13 shows a case where the set pressure equalizing start time is set before the stop command of the compressor 1.
　本実施の形態４では、実施の形態３と同様に、図１１に示すステップＳ２１～ステップＳ２６の処理が行われることにより、均圧制御および回転制動制御が開始される。
　そして、その後、実施の形態２と同様に、図９に示すステップＳ１６～ステップＳ１９の処理が行われることにより、回転制動制御および均圧制御が終了する。 In the fourth embodiment, the pressure equalization control and the rotational braking control are started by performing the processes of steps S21 to S26 shown in FIG. 11 as in the third embodiment.
Then, similarly to the second embodiment, the processing of steps S16 to S19 shown in FIG. 9 is performed, so that the rotation braking control and the pressure equalizing control are completed.
　以上のように、本実施の形態４に係る冷凍装置１００において、均圧制御は、回転制動制御が開始される前に開始され、回転制動制御が終了しても継続される。
　これにより、実施の形態２および３と同様に、高圧部１６と低圧部１５との均圧時間をより短縮することができるとともに、インバータ５の破損を抑制することができる。 As described above, in the refrigerating apparatus 100 according to the fourth embodiment, the pressure equalizing control is started before the rotational braking control is started, and is continued even after the rotational braking control is completed.
As a result, similarly to the second and third embodiments, the pressure equalizing time between the high-voltage portion 16 and the low-voltage portion 15 can be further shortened, and damage to the inverter 5 can be suppressed.
　以上、冷凍装置１００の実施の形態１～４について説明したが、冷凍装置１００は、上述した実施の形態１～４に限定されるものではなく、要旨を逸脱しない範囲内で様々な変形や応用が可能である。例えば、実施の形態１～４では、圧縮機１としてシングルスクリュー圧縮機を適用した場合について説明したが、これはこの例に限られない。圧縮機１として、例えば、２つのスクリューロータを備え、それぞれのスクリューロータの溝部を噛み合わせて圧縮室を形成するツインスクリュー圧縮機が適用されてもよい。また、圧縮機１として、例えば、レシプロ圧縮機、スクロール圧縮機、ターボ圧縮機およびロータリー圧縮機が適用されてもよい。 Although the first to fourth embodiments of the refrigerating apparatus 100 have been described above, the refrigerating apparatus 100 is not limited to the above-described first to fourth embodiments, and various modifications and applications are made without departing from the gist. Is possible. For example, in the first to fourth embodiments, the case where the single screw compressor is applied as the compressor 1 has been described, but this is not limited to this example. As the compressor 1, for example, a twin screw compressor having two screw rotors and engaging the grooves of the respective screw rotors to form a compression chamber may be applied. Further, as the compressor 1, for example, a reciprocating compressor, a scroll compressor, a turbo compressor and a rotary compressor may be applied.
　また、実施の形態１～４において、インバータ５は、圧縮機１と別体で構成されるように説明したが、これに限られず、例えば、インバータ５は、圧縮機１と一体的に構成されてもよい。 Further, in the first to fourth embodiments, the inverter 5 is described as being configured separately from the compressor 1, but the present invention is not limited to this. For example, the inverter 5 is integrally configured with the compressor 1. You may.
　１　圧縮機、１ａ　ケーシング、１ｂ　隔壁、１ｃ　吐出口、２　凝縮器、３　減圧装置、４　蒸発器、５　インバータ、６　制御装置、１０　モータ、１０ａ　ステータ、１０ｂ　モータロータ、１１　スクリュー軸、１１ａ　主軸受、１１ｂ　副軸受、１２　スクリューロータ、１２ａ　スクリュー溝、１３　ゲートロータ、１３ａ　歯、１４　圧縮室、１５　低圧部、１６　高圧部、１７　ストレーナ、１８　逆止弁、２０　連通流路、２１　流量調整弁、６１　比較判定部、６２　駆動制御部、６３　記憶部、７１　処理回路、８１　プロセッサ、８２　メモリ、１００　冷凍装置。 1 compressor, 1a casing, 1b partition wall, 1c discharge port, 2 condenser, 3 decompression device, 4 evaporator, 5 inverter, 6 control device, 10 motor, 10a stator, 10b motor rotor, 11 screw shaft, 11a main bearing, 11b auxiliary bearing, 12 screw rotor, 12a screw groove, 13 gate rotor, 13a tooth, 14 compression chamber, 15 low pressure part, 16 high pressure part, 17 strainer, 18 check valve, 20 communication flow path, 21 flow control valve, 61 Comparison judgment unit, 62 drive control unit, 63 storage unit, 71 processing circuit, 81 processor, 82 memory, 100 refrigeration device.

Claims (9)

  1. 　吸入した冷媒を圧縮機構により圧縮して吐出する圧縮機を備えた冷凍装置であって、
    　前記圧縮機構を駆動するモータと、
    　吸入された前記冷媒が流れる低圧部と、
    　前記低圧部を流れる前記冷媒を圧縮する圧縮室と、
    　前記圧縮室で圧縮された前記冷媒が流れる高圧部と、
    　前記低圧部と前記高圧部とを連通させる連通流路と、
    　前記連通流路に設けられ、前記連通流路を流れる前記冷媒の流量を調整する流量調整弁と
    を有する圧縮機と、
    　前記圧縮機に電圧を供給し、前記モータを駆動または停止させるインバータと、
    　前記インバータおよび前記流量調整弁を制御する制御装置と
    を備え、
    　前記制御装置は、
    　前記圧縮機の運転を停止させる停止制御において、前記インバータを制御して前記圧縮機構の駆動を防止または抑制する制動制御と、
    　前記流量調整弁を開いて前記高圧部と前記低圧部とを均圧する均圧制御と
    を行う
    冷凍装置。     A refrigerating device equipped with a compressor that compresses and discharges the sucked refrigerant by a compression mechanism.
    The motor that drives the compression mechanism and
    The low-pressure part where the sucked refrigerant flows and
    A compression chamber that compresses the refrigerant flowing through the low pressure portion, and
    A high-pressure part through which the refrigerant compressed in the compression chamber flows,
    A communication flow path that communicates the low-pressure portion and the high-pressure portion,
    A compressor provided in the communication flow path and having a flow rate adjusting valve for adjusting the flow rate of the refrigerant flowing through the communication flow path.
    An inverter that supplies voltage to the compressor to drive or stop the motor,
    A control device for controlling the inverter and the flow rate adjusting valve is provided.
    The control device is
    In the stop control for stopping the operation of the compressor, braking control for controlling the inverter to prevent or suppress the drive of the compression mechanism, and
    A refrigerating device that opens the flow rate adjusting valve to perform pressure equalization control for equalizing the pressure between the high pressure portion and the low pressure portion.
  2. 　前記圧縮機構は、
    　前記モータのロータであり、
    　前記制御装置は、
    　前記制動制御の際に、前記インバータを制御して前記ロータの逆回転を防止または抑制する
    請求項１に記載の冷凍装置。     The compression mechanism
    The rotor of the motor
    The control device is
    The refrigerating device according to claim 1, wherein during the braking control, the inverter is controlled to prevent or suppress the reverse rotation of the rotor.
  3. 　前記制御装置は、
    　前記制動制御の期間と同一期間に前記均圧制御を行う
    請求項１または２に記載の冷凍装置。     The control device is
    The refrigerating apparatus according to claim 1 or 2, wherein the pressure equalization control is performed during the same period as the braking control period.
  4. 　前記制御装置は、
    　前記制動制御が終了しても前記均圧制御を継続する
    請求項１～３のいずれか一項に記載の冷凍装置。     The control device is
    The refrigerating apparatus according to any one of claims 1 to 3, wherein the pressure equalization control is continued even after the braking control is completed.
  5. 　前記制御装置は、
    　前記制動制御の開始前に前記均圧制御を開始する
    請求項１～４のいずれか一項に記載の冷凍装置。     The control device is
    The refrigerating apparatus according to any one of claims 1 to 4, wherein the pressure equalization control is started before the start of the braking control.
  6. 　前記制御装置は、
    　前記インバータを制御して、前記圧縮機の運転周波数が運転時の周波数よりも低い設定周波数となった場合に、前記制動制御を行う
    請求項１～５のいずれか一項に記載の冷凍装置。     The control device is
    The refrigerating device according to any one of claims 1 to 5, wherein the braking control is performed when the operating frequency of the compressor becomes a set frequency lower than the operating frequency by controlling the inverter.
  7. 　前記制御装置は、
    　前記圧縮機の運転周波数を低下させるように、前記インバータを制御して前記制動制御を行う
    請求項１～６のいずれか一項に記載の冷凍装置。     The control device is
    The refrigerating apparatus according to any one of claims 1 to 6, wherein the inverter is controlled to perform the braking control so as to lower the operating frequency of the compressor.
  8. 　前記連通流路は、
    　前記圧縮機の外部に設けられている
    請求項１～７のいずれか一項に記載の冷凍装置。     The communication flow path is
    The refrigerating apparatus according to any one of claims 1 to 7, which is provided outside the compressor.
  9. 　前記連通流路は、
    　前記圧縮機の内部に設けられている
    請求項１～７のいずれか一項に記載の冷凍装置。     The communication flow path is
    The refrigerating apparatus according to any one of claims 1 to 7, which is provided inside the compressor.
PCT/JP2019/023880 2019-06-17 2019-06-17 Freezing apparatus WO2020255198A1 (en)

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US17/603,648 US20220235987A1 (en) 2019-06-17 2019-06-17 Freezing device
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EP3985327B1 (en) 2023-09-20

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